E-ISSN:2456-3110

Review Article

Samana Vayu

Journal of Ayurveda and Integrated Medical Sciences

2023 Volume 8 Number 6 June
Publisherwww.maharshicharaka.in

A critical review on Samana Vayu apropos regulation of Gastrointestinal Tract

Tripathi R.1*, Dubey S.2, Prasad N.3
DOI: http://dx.doi.org/10.21760/jaims.8.6.24

1* Ritunanda Tripathi, Assistant Professor, Department of Kriya Sharir, MAMC, Bhopal, Madhya Pradesh, India.

2 Shuchi Dubey, Reader, Department of Kriya Sharir, PTKLS Govt (Auto.) Ayurveda College, Bhopal, Madhya Pradesh, India.

3 N.K. Prasad, Professor & HOD, Department of Kriya Sharir, SIARAM, Bhopal, Madhya Pradesh, India.

Ayurveda believes in the theory that whatever is present, in the external universe is also present in the human body. Understanding the factors that constitute the body provides knowledge regarding the factors which are responsible for its well-being. The complete physiological action of the body can consolidate in Dosha, Dhatus, and Malas, these three are the main constituents of the body. The Tridoshas", control the fundamental physiological functions of the body. Vata being supreme among the three Doshas, conducts and controls all the activities of the body through Vayu. The Samana Vayu lies near the Jatharagni and its Sancharsthan (effective area) is Kostha; its function is Grahana, Pachana, Vivechana, and Munchana of Anna Dravya and providing strength to Agni. Prana, Samana, and Apana are three types of Vayu, that assist Jatharagni in the process of Anna Pachana. In modern science, a lot of research has been done regarding the factors participating in the regulation of the gastrointestinal tract such as enzymes, hormones, nerves, etc. However, the exact role of Samana Vayu in the regulation of Agni and consequent absorption of different food materials and metabolism followed by excretion, etc. is not properly understood in Ayurveda, leading to confusion between the functions of Samana Vayu, Pachaka Pitta, Kledaka Kapha and even up to the excretory functions of Apana Vayu. This study aims to understand the role of Samana Vayu in the physiology of Pachana through Agni and its regulatory mechanism.

Keywords: Samana Vayu, ENS, Gastric Reflexes, Prana Vayu, Apana Vayu, Agni

Corresponding Author How to Cite this Article To Browse
Ritunanda Tripathi, Assistant Professor, Department of Kriya Sharir, MAMC, Bhopal, Madhya Pradesh, India.
Email: 		Ritunanda Tripathi, Shuchi Dubey, N.K. Prasad, A critical review on Samana Vayu apropos regulation of Gastrointestinal Tract. J Ayu Int Med Sci. 2023;8(6):141-151.
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https://jaims.in/jaims/article/view/2516

Manuscript Received Review Round 1 Review Round 2 Review Round 3 Accepted
2023-05-01 2023-05-03 2023-05-10 2023-05-17 2023-05-24
Conflict of Interest Funding Ethical Approval Plagiarism X-checker Note
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© 2023by Ritunanda Tripathi, Shuchi Dubey, N.K. Prasadand Published by Maharshi Charaka Ayurveda Organization. This is an Open Access article licensed under a Creative Commons Attribution 4.0 International License https://creativecommons.org/licenses/by/4.0/ unported [CC BY 4.0].

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Introduction

Ayurveda is the ancient eternal science of life and longevity. It is a system of medicine as well as a general philosophy of health and wellness. It aims to maintain the health of healthy individuals and preventions of diseases.[1]

Dosha, Dhatu, and Mala are given immense importance in contrast to the formation and maintenance of the body. Doshas are the main bio-energies that control all physiological activities; in a state of equilibrium, they are responsible for maintaining a normal and healthy state of the body. They are very important for our body both physiologically and pathologically because vitiated Doshas can vitiate Dhatus and Malas and ultimately cause many diseases.

Digestion is important for breaking down food into nutrients, which the body uses for energy, growth, and cell repair. Food changes into smaller molecules of nutrients before the blood absorbs them and then it carries them to the cells throughout the body. The body elements indeed remain deprived of nutrients, until the food is properly digested by Agni.[2] Proper digestion is the first requirement for the maintenance of body homeostasis because diet influences the physiological units of the body.

The Annawaha Srotas in the body is the channel that carries the food undergoing chemical-biochemical and metabolic changes. It provides the body with a frequent supply of nutrients water and electrolytes. Digestive secretions serve to chemically alter the components of food (particularly macromolecules) such that their constituents can be absorbed across the epithelium. The GI tract, the key interface between ingested nutrients and the body, plays a critical role in regulating energy homeostasis.[3]

Prana, Udana, Samana, Vyana, and Apana five types of Vayu perform different physiological functions. Samana Vayu supports the Agni and together they play a crucial role in the process of digestion. The Samana Vayu lies near the Jatharagni and its Sancharsthan Kostha; its function is Grahana, Pachana, Vivechana, and Munchana of Anna Dravya and gives strength to Agni.[4,5]

Agni plays a major role in the process of digestion and metabolism. According to Ashtanga Hridaya "Rogah Sarveapi Mandaagnau" and

"Kayasyantargneshchikitsa Kayachikitsa" i.e., all types of diseases are due to Mandagni and Kayachikitsa is the branch of Ayurvedic science which deals and rests on the concept of Jatharagni. Samana Vayu promotes Agni but whenever Samana Vayu is vitiated it also vitiates Agni and causes disease related to Agnisad.

Aim

To study the concept of Samana Vayu and find out the correlation between Samana Vayu and regulation of the gastrointestinal tract.

Materials and Methods

Conceptual study based on classical references, modern literature and published research articles.

Review of Literature

The term Samana means "Samanthad Kosthe Samyak Samam Vaa Aniti, Iti Samanah”, which denotes prevalent all around or which equalizes into one whatever we eat.[6] Samana Vayu resides in the Kostha, digests the ingested food and produces Dhatus and Malas.[7] Its function is to balance, carry and controlling of the food.

Role of three Vayu in digestion
Prana, Apana, and Samana, the three types of Vayu when residing in their abode stimulate Jatharagni which causes the digestion of food. According to modern Science The whole digestive movements are controlled by various segments of the nervous system. Out of the five types of Vayu, the Prana Vayu helps in mastication and deglutition, Samana Vayu remaining in the stomach, duodenum and intestine helps in churning, segmentation, digestion, and the Apana Vayu helps in the retaining as well as outgoing activity of the digestive food material (i.e., defection) from the sigmoid colon and the rectum.[8]

If the food is ingested properly, it is pulled into the Kostha (alimentary tract) by Prana Vayu, larger particles are split up into smaller ones by the fluids and made soft by their unctuousness (moistness), then cooked (digested) by the Antaragni activated by Samana Vayu inside the Amashaya.[9] When these five types of Vayus present in a particular place that is different from their own and when impaired, they afflict the body with diseases specifically in their locations and functions. This may also lead to instantaneous death.[10]


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Location and functions of Samana Vayu

SN Acharyas Location (Sthan) Functions (Karma)
1.  Charaka Samhita[16]   lies beside the Agni, Sweda, Dosha and Ambuvaha Srotas the promoter of Agni and vitality, regulates the channels carrying sweat, waste matter and water
2. Sushruta Samhita[17]     associates with Agni, in the organ where ingested food is undergoing digestion digests food and separates its product; its vitiation causes Agnisad, Gulma, Atisar etc.
3. Astang Hridaya[18]   stays near the Agni, and Sanchar Sthan is Kostha. Grahana, Pachana, Vivechana and Munchana of ingested food.
4. Sharangdhara[19]   navel (umbilicus) as the prime location the Samana Vayu is helpful in the circulation of blood.[20]
5. Bhavaprakash[21] Kostha, the navel region, associated with Agni digests food, transport to the duodenum and separates its products.[22] helps the feces to transport to the rectum after that Apana Vayu does its work.[23]
6. Bhela Samhita[24]   pervades all over the body maintains coordination in the entire body.
7. Sharir Tatwa Darshnam Naam Vatadi Dosh Vigyanam[25] transmits through the subtle sources (Sukshma Srotasas) of the muscles in the intestine (Kshudrantra) and Pakwashaya (colon). contraction and relaxation of the intestine, take the food from the stomach into the duodenum (Pachyamanashaya), stimulate the Pachaka Pitta present in the fluid form in the Kshudrantra, stimulates and carries Sara Bhaga to the liver and spleen by Rasavaha Srotas and carries the Kitta Bhaga (feces and urine) to the Pakwashaya and Mutrawaha Srotasas, from Pakwashaya throws the Purisha (feces) out of the body.[26]
8. Astang Samgrah[27] Kostha, near the Agni circulates Dosha, Mala, Shukra and Artav Vahi Srotas holds food in the GI tract, digestion of food, separate into absorbable and non-absorbable portion and sends it further in the lower part of the intestine.[28]  
9. Vaidyakiyashubhashita Sahityama,[29] Yoga Science Manipura Chakra (Solar plexus) responsible for intestinal motility and digestive secretions (Agni).

Relation between Agni and Samana Vayu

The bio-energy of the body is Agni. The word 'Sama' is understood to mean Samana Vayu "a helper of Agni". When the Samana Vayu residing in the naval region is located in its place, then Jatharagni is in a balanced state. Samana Vayu Vitiated from its abode, the Agni, vitiates and becomes Vishama, when the Agni is affected by Pitta, it becomes Teekshna and when Agni is obscured with Kapha, it becomes Manda (dull).[11,12]

The Vishama Agni (enzymes responsible for digestion and metabolism) cause irregularity in the digestion of food, thereby leading to discordance of tissue elements while Manda Agni causes poor digestion. The Teekshna Agni causes depletion (Shoshana) of the tissue elements.[13]

If the Agni is in its normal state and if the individual takes an appropriate quantity of food, then there will be proper digestion of food, which leads to the maintenance of the equilibrium of tissue elements.[14] For the maintenance of equilibrium of the tissue elements, the Agni must be in its normal state and this condition of the Agni is maintained with the help of Samana Vayu. Simultaneously, Pitta and Kapha should be in a state of equilibrium for the normal functioning of Agni.[15]

Discussion

Homeostasis and equilibrium of the Tridoshas are fundamental pillars of health. Among the Tridoshas, Vata has primarily been referred to as "Vayusyantatantradharah" which is the primal constituent of the living body and it is holding both the structure and functions of living beings. It has been mentioned that Samana Vayu is Agni Sameepastha, which means near to Agni or digestive fire, and further stated that it is responsible for the movement in the Koshtha (abdomen). In this regard, the Ashtanga Hridaya has acknowledged the effect of Samana Vayu in the entire process of digestion from intake of food to its removal (in form of Anna Grahana, Pachana, Vivechana, and Munchana). This entire process of transforming food materials into assimilable form is known as Pachana (digestion) as explained in modern science also.

After digestion, Rasa reaches the heart where it gets distributed to the whole body because only Rasa provides nutrition to the entire body. Acharya Sharangadhara opines that after digestion Samana Vayu (Samanomaruteritah) sends Rasa to the heart[30] and Vyana Vayu from the heart to the whole body. The Samana Vayu helps the Jatharagni to digest the food and also in the separation of Sara and Mala parts. Rasa Dhatu in one month is transformed into Shukra and Artava by Agni and in turn for Kshaya and Vriddhi of Dhatus. In this way, Samana Vayu is not only limited to the digestion of the food, but it also contributes actively to the process of proper formation of Shukra and Artava.

Many neurons of the enteric nervous system are components of GI reflex pathways that regulate gastrointestinal secretion and motility in response to stimuli present in the lumen of the gastrointestinal tract. The initial components of a typical gastrointestinal reflex pathway are sensory


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receptors (such as chemoreceptors and stretch receptors) that are associated with the sensory neurons of the ENS. The axons of these sensory neurons can synapse with other neurons located in the enteric nervous system, central nervous system, or autonomic nervous system, informing these regions about the nature of the contents and the degree of distension (stretching) of the gastrointestinal tract.

Regulatory functions of the Samana Vayu

The main function of the Samana Vayu is Annam Grahanati, Pachati, Vivechayati, and Munchati, which describes the sequential events happening once after the consumption of food by a person, i.e., it explains the whole process of digestion in the GI tract right receptive relaxation of stomach to excretion in a systematic manner. Elaborating the individual processes (Samana Vayu) along with their resemblance in the digestion process.

Deglutition and retention of food (Annama Grahnati)

Ingestion of food is called 'Anna Pravesha' and Grahanti means receiving and retention of food in the gastrointestinal tract. Food once taken in bolus form gets mixed with saliva in the mouth. Chewing is a process in which the food particles get mixed with salivary secretion helps in the movement of the bolus. During this activity, the perception of Rasa is done by Rasendriya whereas Bodhaka Kapha is responsible for the exact taste. The food then further passes through the esophagus by peristaltic movements as it makes its way further to Amashaya.[31] These series of events are assisted by Prana Vayu as deglutition is the function of Prana Vayu - "Uraha Kanthachara" as it helps in action of inhalation, exhalation, and swallowing. The location of Prana Vayu is Murdha, Kantha, and Jihwaadi and helps to Aharadi Karma, taken as deglutition and retention (Dharana) both. The function of Prana Vayu is Purana which means passing down food with proper receptacles. Acharya Vagbhatta supported the view of control both activities. According to Acharya Dalhana, Prana, Apana, and Samana is helpful in digestion and perform together Dhmapana and Palana Karma in the whole body.[32] Sthivana, Kshavathu, Udgara, Aharana etc. are the Prana Vayu and controlled expulsion of Shukra, Artava, Purish, Mutra, Garbha are the functions of Apana Vayu.

Swallowing is activating centrally and is coordinated with a peristaltic wave along the length of the esophagus that propels the food bolus to the stomach.[33] It can be divided into three stages and can be substantiated as Prana Vayu: - First the voluntary stage which is a voluntary action. The second pharyngeal stage is mainly a reflex act, initiated by the voluntary movement of food into the back of the mouth which results evoke the swallowing reflex. Third oesophageal stage, the trachea is closed and the esophagus is opened, then rapid-peristaltic wave initiated by the nervous system of the pharynx sends the bolus of food into the upper esophagus. The areas in the medulla and lower pons (Murdha) control the swallowing process.

The last part of deglutition wherein the oesophageal stage of swallowing is an involuntary action, probably the functions of Saman Vayu starts from here. Thus, we can say that the ingestion of food is a process done through the coordination of Prana Vayu and Samana Vayu.

Digestion of food (Annama Pachati)

Annam Pachati means digestion of food; it is mainly the function of Agni. After the action of Jatharagni on ingested food, it gets assimilated in the body. Samana Vayu is responsible for the stimulation and balanced condition of Agni and eventually Pachati Karma.

The ingested food is transformed in the gastrointestinal tract and gets converted into Ahara Rasa. This process is affected by some factors that are called Aahara Parinamakar Bhava. These are six Bhavas i.e., Ushma, Vayu, Kleda, Sneha, Kaal, and Samyoga, amongst which Vayu is one responsible for all the movements and secretions of the Gastrointestinal tract.[34] While Sneha and Drava are property of Kledaka Kapha, making bolus soft for easy digestion; the transportation mechanism of the digestion is controlled by Vayu i.e., Prana, Samana, Vyana, and Apana Vayu. Sama Vayu also plays a major role in digestion of food by kindling Agni. Vyana Vayu is also responsible for contractions and relaxations of the skeletal muscles in the whole body as well as the sphincter of the GI Tract. As per Vagbhatta, it is helpful to the separation of nutrients and wastes part of the food after digestion and supplies nutrients to the entire body.


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The Samana Vayu brings the food near to Agni and also helps in the further process like digestion and assimilation. The various movements in the gastrointestinal tract viz. peristalsis, segmentation, and mixing movements of food to carry forward and secretion of gastric juices and enzymes which assist the digestion are done by Samana Vayu.

Food is stored in the stomach and gets mixed gastric secretions which are further known as chyme then it proceeds to the small intestine (Grahani) where the final digestion and absorption process takes place. The movements of the Amashaya are basic electrical rhythm, hunger contractions, receptive relaxation, and peristalsis. There is a certain difference in anatomical structure secretions and movement from the stomach to the small intestine.

Samana vayu circulating in the whole gastrointestinal tract stimulates the Agni or Pachaka Pitta and controls the movement of Amashaya, Grahani, and Pakwashaya. It is also present in the layer of intestinal muscles through peristaltic movement the food will be brought near the Agni. Due to contractions and relaxations of muscles (Saman Vayu), glands present in the inner layer of the small intestine contract and secrete enzymes, juices, and hormones (Pachaka Pitta collectively) and release the secretions into the lumen.

The hormones are peptides produced by enteroendocrine cells in the digestive tract and they reach their target organs by distribution in the circulatory systems (Vyana Vayu). Gastrin (Pitta) is secreted by the stomach in response to stimulus connected with the ingestion of food products of proteins (Prana Vayu) and it stimulates gastric acid secretion (Pachaka Pitta). Cholecystokinin is secreted by the mucosa of the duodenum and jejunum mainly in response to digestive products of fat (Snehamsha) in the intestinal contents; it contracts the gallbladder, expelling bile (Pitta) into the small intestine (emulsifying fatty substances - Kledana) and inhibits stomach contraction. Secretin is secreted by the mucosa of the duodenum in response to acidic gastric juice emptying into the duodenum from the pylorus of the stomach (Agnivardhana Karma). Its action promotes pancreatic secretion of bicarbonate which in turn helps to neutralize the acid present in the small intestine.

Peristalsis (Apakarshana) is mainly performed by Samana Vayu and can be compared with gastrointestinal peristalsis. Peristalsis is a reflex response that is initiated when the gut wall is stretched by the content of the lumen and it occurs in all parts of the GI tract from the esophagus to the rectum. Peristalsis is a good example of the integrated activity of the enteric nervous system. It appears that local stretch release serotonin which activates the myenteric plexus.

The myenteric plexus secretes neurotransmitters acetylcholine and substance P which makes the contractions of smooth muscles present behind the bolus (Prana & Samana Vayu). At the same time, NO and VIP (vasoactive intestinal polypeptide) make the muscle relax present in the front of the bolus.[35]

The peristaltic wave of the lower two-thirds of the esophagus is strongly controlled by the Vagus nerves acting through connections with the oesophageal myenteric nervous system (Samana Vayu). When the vagus nerve is cut to the esophagus, the myenteric nerve plexus of the esophagus becomes excitable enough after several days to cause strong secondary peristaltic waves even without support from the vagal reflexes. Consequently, even after paralysis of the brain stem's swallowing reflex, food fed by a tube into the esophagus still passes easily into the stomach.[36]

The vagus nerve affects the contraction of Amashaya which is connected to the myenteric plexus. Receptive relaxation is coordinated by the enteric nervous system and vagus nerve (Samana and Prana Vayu respectively).

The presence of food in the lumen acts as a stimulus (Sparsha Nimitta). Sparsha is an attribute of Vayu and sensory information is also received by Vayu. (Vaishesik Sutra) Myenteric nerves are stimulated by Sparsha Guna of Vata. The Panchbhautika organization of Vayu is a mixture of many gases like oxygen, nitrogen, etc. NO, and CO is gaseous molecules that act like a neurotransmitter (surface receptor).[37] The relaxation of the sphincter and muscles due to these gases, there is strong evidence of the presence of Vata. In this way, we can say that the neurotransmitter activity in the gastrointestinal tract can be considered as the functions of Vata.




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The activities of the digestive gland are coordinated by both neural and hormonal mechanisms. These regulatory mechanisms are centred around the duodenum (Samana Vayu), for it is there that acid must be neutralized and the appropriate enzymes must be added (Pachaka Pitta).[38] The endocrine cells of gastric mucosa run very close to the nerve fiber and also play a vital role in mucosal control. These endocrine cells take action in the luminal environment and release messenger (neurotransmitter) tissue of mucosa where nerve endings are found. That important is with serotonin-containing endocrine cells which activate motility reflexes.

Gastric and intestinal motility puts pressure on cells because of this it secretes gastric juices and enzymes. Similarly, the Samana Vayu stimulates the Jatharagni by motility and secretions. From the action of Jatharagni formation of Ahara Rasa takes place which consists of various types of nutrients and electrolytes.

Effect of Samana Vayu on different stages of Paka

Avasthapaka is the change in the state or form of food substance in the Amashaya and Pakwashaya in the process of digestion. It is divided into two phases the Prapaka and Vipaka, in which "Prapaka" has been defined as the first change and "Vipaka" as changes that the food has undergone.[39]

The term Annapravesha means the entry of food into the mouth, the perception of taste is under the influence of Bodhaka Kapha (saliva) dissolves the substance, provides an appropriate medium for the enzyme to their function and lubricates the food for easy swallowing.[40,41]

Amashaya is the place where the maximum part of digestion is completed. There it is mixed and disintegrated by juices and secretion of the stomach (Kledaka Kapha), that result moistens the food material.[42] Kledana is the transformation of food, it is one of the important parts of digestion as owing to this process the food particles are divided into small particles (Bhinnasamghata) and the food becomes easily assimilable (Sukhajarobhavati).[43] In this stage the Ahara Rasa is formed, elements Kapha Dosha is secreted and makes the food soft, this is the Madhura Awsathapaka.


The process of the synthesis of the food is also assisted by the constant churning process carried out due to the movement of the muscles of the Amashaya (Samana Vayu). This constant involuntary movement of the Amashaya helps in the fine churning and mixing of Kledaka Kapha with ingested food. The intake of food stimulates the secretion of Pitta in the Amashaya. The Madhur Bhava of the Avastha Paka is seen to be abolished by the hydrochloric acid secreted by the cells of the mucus membrane of the stomach. This makes the beginning of the Amalabhava or the acid phase of Prapaka.

The Amla Avasthapaka is further continued under the influence of Jatharagni, resulting in the final breakdown of various constituents of the food. As Charaka described that the food reaching Amashaya is fully digested, is distributed to the entire body by Dhamanis analogous to blood vessels and lymphatics in the villi of the small intestine, through which the absorbed food is transported to the liver, from there it is distributed to all the parts of the body through the circulating channels, for proving nourishment to tissues (Vyana Vayu).

The second stage of Avasthapaka can be correlated to expulsion of acidic chyme from the pyloric sphincter to the first part of the duodenum till absorption. The result of complete gastric digestion is acidified chyme, defined by Charaka as Vidagdha, and referred to by the Chakrapanidatta as 'Kinchitapakwakinchitaapakwa" which means partially digested.

This entire area comprises digested and undigested food (Vidagdhasyeti Pakwapakwasya). Hence it extends to the second part of the ileum almost. Over here, pancreatic and hepatic secretions along with succus entericus, in form of Pitta digest all food components. This makes digested part of the food to be separate from the undigested part of the food.

The catalysts or enzymes which break down complex substances into simple ones during catabolism and liberate energy can be included in Pitta Dosha because substances of the Pitta group are involved in breaking down complex substances into simple ones with the evolution of heat.[44]

The aspect of Avasthapaka can be seen form of peptic digestion of proteins. The Bhutagni, Dhatvagni, and Jatharagni are responsible for proper digestion as well as metabolism.


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Pitta is known as body heat and performs actions related to Agni such as heat, digestion, and transformation. Pachaka Pitta digests the food, separates the Rasa, Purisha, and Mala, and empowers the other Pitta with its power.

In third stage (Katu Awastha Paka), Katu Rasa is produced and Vata is generated. Further digestive events occur in the Pakwashaya as the material passing through the Amashaya reaches the Pakwashya, which is dried by heat and bound as a lump. In this process, Katu Vayu is produced.[45] Chakrapanidutta states that feces are produced in the form of lumps in this process (Paripinditapakvasya) and pungent Vayu arises during the process of forming lumps (Vayuhsyatkatubhavatah).

Role of Samana Vayu during Pachana Kala and Bhojanantar Kala Prakarsh

When the meal is present in the lumen, the enteric nervous system promotes the segmentation contraction which provides the ample mixing of the intestinal contents (chyme) with gastric juices (Kledaka Kapha and Pachaka Pitta Samsarga). The membrane potential of the majority of gastrointestinal smooth muscle sustains rhythmic fluctuations that sweep along the length of the gut. The rhythm varies in different parts of the gut (segments) and is acknowledged by pacemaker cells known as interstitial cells of Cajal. This basic electrical rhythm (BER) provides for sites of muscle contraction when stimuli superimpose spike potentials on the depolarizing portion of the BER waves.[46]

In the period between meals, the intestine is relatively inactive, so it is swept through by a large peristaltic wave triggered by the hormone motilin. There are migrating motor complex that presumably serves a "housekeeping" function.

Separation and absorption of food (Annam Vivechayati)

It means the separation of Sara (useful) and Kitta (waste) products from digested food. Water, minerals, etc. are present in the essence of the digested food which gets absorbed and feces, urine, etc. are expelled from the body. This function of separation is known as Vivechan.

A segment of the bowel contracts at both ends and then a second contraction occurs in the centre of

the segment to force the chyme both backward and forward. These mixing patterns continue for as long as nutrients remain in the lumen to be absorbed (Vivechana). It is centrally reflecting the proximal activity of the bowel directed by the enteric nervous system and can also do its function independently of central input.

These observations correlate with modern research that deals with the formation of Purisha, according to which products are digestion are absorbed through the small intestine as well as many other compounds such as vitamins and mineral salts. This material reaches the large intestine, and the process is generally complete except for the absorption of water. Here, the chyme is transformed into a solid form by the Agni (Shoshyamanasya). In the large intestine, more water and salt are absorbed and the remaining material is now converted into the Purisha which excretes the body.

Chakrapani opines that Vayu disorders occur initially occurs in Pakavashaya and their treatment is also difficult. The treatment here can also Shaman (palliative).[47] If neural control of this system is disturbed, then peristaltic movement is affected, causing accumulation of waste products and fermentation gases, as a result of this accumulation toxins is absorbed into the system; the generalized, as well as local manifestations of the nervous system, exist.

The consistency of Purisha depends largely on the process of water absorption. It should be noted that the stability of feces also depends on factors such as gastrointestinal motility and the nature of the diet.

Expulsion of waste (Munchati)

Elimination of waste products is the function of Apana Vayu. Samana Vayu initiates Apana Vayu to accomplish its function for the expulsion of waste products (removal of feces and urine from the body).

Distension of the stomach by food commences contractions of the rectum and constantly a desire to defecate. The response is called the gastrocolic reflex and may be augmented by the action of gastrin on the colon. Samana Vayu can be seen as ENS based on functions that control the entire gastrointestinal tract, especially gastrointestinal reflex pathways.


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It supports the three types of reflexes; first, that is integrated entirely within the gut wall (control gastrointestinal secretion, peristalsis, and mixing contractions), second from the gut to the prevertebral sympathetic ganglia, and after that back to the GI tract (a) the gastrocolic reflex- signals from the stomach to cause evacuation of the colon, (b) the enterogastric reflex -signals from the colon and small intestine to inhibit stomach motility and secretion, (c) the colonoileal reflex- from the colon to inhibit emptying of ileal contents into the colon) and third, from the gut to the spinal cord or brain stem and then back to the gastrointestinal tract(to control gastric motor and secretory activity, the inhibitory effect of the entire GI tract, and defecation reflex).

Re-absorption of water is an important function of the large intestine. In addition to absorbing water, the large intestine absorbs the number of other substances that remains faecal material secreted into the digestive tract along its length. Movements from the caecum to the transverse colon appear very slowly, allowing hours for water absorption to convert the already thick material into the Pindarupa (sludgy paste).

The parasympathetic nervous system is capable of stimulating the enteric nerves to enhance enteric functions. Parasympathetic enteric neurons participate in defection and provide a rich nerve supply to the sigmoid, colon, rectum, and anus.

Prana is the first manifestation of life which integrate with Apana and stimulate the living beings, thus Prana and Apana are mentioned as the first two signs of life.[48] Acharya Susruta has called Pakwashaya the place of Apana and from this place, Purisha moves downward.[49] Thus, Samana Vayu moves in Kostha and regulates the process of digestion and absorption of body fluids i.e., Sara Kitta Vivechana.

The next stage of excretion of the waste out of the body is the function which is mainly derived from the Apana Vayu. When feces enter the rectum, distention of the rectal wall initiates afferent signals that spread through the myenteric plexus (Samana Vayu) to initiate peristaltic waves in the descending colon, sigmoid, and rectum, pushing feces toward the anus. As the peristaltic wave reaches the anus, the internal anal sphincter is relaxed by inhibitory signals from the myenteric plexus; the external anal

sphincter voluntarily relaxed (Apana Vayu) at the same time, defecation occurs.[50] The intrinsic myenteric defecation reflex functioning is relatively weak, so another type of defecation reflex (parasympathetic defecation reflex involving the sacral segment of the spinal cord) begins for effective defecation. It can be said that the Samana Vayu appears as a regulating factor for Jatharagni, but Pitta and Kapha have an important role to play in the digestive process because Samana Vayu alone cannot do this work properly.

The neurons of the enteric nervous system (Samana Vayu), central nervous system (Prana Vayu), or autonomic nervous system (Vyana Vayu) subsequently activate or inhibit gastrointestinal glands and smooth muscle, altering GI secretion and motility.

Conclusion

Samana Vayu is present throughout the Mahasrotas (GI Tract) as a regulating mechanism for food transformation. It is responsible for Grahana and Pachana (motility and secretions), Sara-Kitta Vivechana (separation and absorption), and Munchana (pushing feces onward) of Anna Dravya. It strengthens Agni and affects (Anugraha) the entire body through Palana Karma.

Samana Vayu brings food near Agni for a specific duration and holds it in the Amashaya, Pachyamanashaya, and Pakwashaya respectively. During the process of deglutition, the lower two-thirds of the oesophagus are strongly controlled by the vagus nerves, which act through connections with the oesophageal myenteric nervous system. This action can be considered under the control of Samana Vayu, while the first two parts come under Prana Vayu. It is a component of gastrointestinal reflex pathways that regulate GI secretions (Agni) and motility in response to stimuli present in the lumen of the GI tract (Samanoagnibalapradah). Individual fibers of muscularis mucosa extend into the intestinal villi and cause intermittent contractions, increasing the surface area exposed to the chyme and enhancing the absorption process (Shoshyamanasya). These contractions, mediated by enteric nerve reflexes, can also be considered as functions of Samana Vayu.

Samana Vayu enables Pakwashaya to produce peristalsis that pushes feces toward


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the rectum and anus. Mass peristaltic movement initiates the defecation reflex, known as the "intrinsic reflex," which is mediated by the local enteric nervous system in the rectal wall. The "parasympathetic defecation reflex," involving the sacral segment of the spinal cord, is also related to the functions of Samana Vayu. The role of the enteric nervous system in the defecation process is associated with Apana Vayu.

The functions of gastrointestinal local hormones can be correlated with Pachaka Pitta (Agni). In this context, Samana Vayu can be considered as a stimulus for hormonal regulation in the gastrointestinal tract. Some chemicals, such as acetylcholine and serotonin, are secreted by nerves and glandular cells of the mucosa, acting as neurotransmitters (paracrine fashion), and may affect small segments of the gastrointestinal tract. Their functioning can be partially attributed to Samana Vayu.

In conclusion, Samana Vayu can be mainly correlated with the nervous regulation of the gastrointestinal tract, including the enteric nervous system, gastrointestinal reflexes, and gastrointestinal hormonal regulation. Paracrine hormones stimulated by the enteric nervous system can also be understood as functions of Samana Vayu to some extent.

Reference

1. Shastri Pt. Kashinath Editor, Charaka Samhita of Vidyotini Hindi Commentary, Sutra Sthan Ch.30, Ver. 26, Vol. 1st, Varanasi Chaukhambha Bharti Academy, Edition 2003, pg. 587.

2. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 Ver. 5, Vol.4, Varanasi, Chaukhambha Sanskrit Series Office, Edition Reprint 2018, pg. 3.

3. Barrett, Kim E. Editor Ganong's Review of Medical Physiology, Twenty-Fifth Edition, 2016, McGraw-Hill Education, pg. 473.

4. Tripathi Brahmanand, Editor Ashtang Hridayam of Vagbhatta Nirmala Hindi Commentary, Sutra Sthan, Ch. 12 Ver. 8, Delhi, Chaukhambha Sanskrit Pratisthan, Edition Reprint 2003, pg. 171.

5. Shastri Pt. Kashinath, Editor Charaka Samhita of Vidyotini Hindi Commentary, Chikitsa Sthan, Ch. 28

Ver. 8, Vol.2, Varanasi Chaukhambha Bharti Academy, Edition 2006, pg. 777.

6. Tripathi Brahmanand, Hindi Commentary Charak Chandrika on Charak Samhita, Ch. 28 ver.8, pg. 935

7. Dev Raja Radhakant, Shabdakalpdruma, Chaturtha Khanda, Naga Publishers, Edition Reprint 1987, pg. 342

8. Shastri Kaviraj Ambika Dutta, Editor Susruta Samhita of Ayurveda Tattva Sandeepika Hindi Commentary, Sutra Sthan, Ch. 35 Ver. 33, Varanasi, Chaukhambha Sanskrit Sansthan, Edition reprint 2005, pg. 134.

9. Murthy K. R. Shrikant, Editor Asthang Sangrah of Vagbhatta, Sharir Sthan, Ch. 6 ver. 57, Vol. 2, Varanasi, Chaukhambha Orientaliya, Edition 1996, pg. 82.

10. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 28 Ver. 12, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg. 22.

11. Tripathi Brahmanand, Editor Asthang Hridayam of Vagbhatta Nirmala Hindi Commentary, Sharir Sthan, Ch. 3 Ver. 73, Delhi Chaukhambha Sanskrit Pratisthan, Edition 2003, pg. 380.

12. Vaidya Lal Chandra Shastri, Editor Asthang Sangrha of Sarvang Sundari Hindi Commentary, Sharir Sthan, Ch.6 Ver. 80, Vaidyanath Ayurveda Bhawan Pvt. Ltd., Edition 1989, pg.199.

13. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 ver. 50, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg. 27.

14. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 ver. 51, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg. 27.

15. Gaud Prof. Banwarilal, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 ver. 51, Delhi, Rashtriya Ayurved Vidyapeeth, Edition 2011, pg. 823.

16. Shastri Pt. Kashinath, Editor Charaka Samhita of Vidyotini Hindi Commentary, Chikitsa Sthan, Ch. 28 Ver. 8, Varanasi, Chaukhambha Bharti Academy, Edition Reprint 2006, pg.777.


Journal of Ayurveda and Integrated Medical Sciences 2023;8(6)149
Tripathi R et al: Samana Vayu apropos regulation of Gastrointestinal Tract

17. Sharma P.V., Editor Sushruta Samhita of Dalhana Commentary, Nidana Sthana, Ch. 1 Ver. 16, Chaukhmbha Vishwa Bharti, Edition 2013, pg. 6.

18. Tripathi Brahmananda, Editor Ashtanga Hridaya of Vaghbhatta, Sutra Sthan, Ch.12 Ver. 8, Delhi, Chaukhmbha Sanskrit Pratisthan, Edition Reprint 2003, pg. 171.

19. Shastri Pt. Parushram, Vidya Sagar, Editor Sharangdhara Samhita of Adhamalla Dipika, Kasiram Gudhartha Dipika Commentary, Purva Khand, Ch. 5, Varanasi, Chaukhambha Orientaliya, Edition 2018.

20. Tripathi Brahmanand, Editor Sharangdhara Samhita of Dipika Hindi Commentary, Purva Khand, Ch. 6 Ver. 13, Varanasi Chaukhambha Sur Bharti Prakashan, Edition 2017, pg. 54.

21. Mishra Brahma Shankar, Editor Bhavprakash of Hindi Commentary, Purva Khand, Garbhprakaran, Vol. 1, Ch. 3, Ver. 109, Varanasi, Chaukhambha Sanskrit Sansthana, Edition 10th, pg. 36.

22. Mishra Brahma Shankar, Editor Bhavprakash of Hindi Commentary, Purva Khand, Ch. 3, Ver. 113,166, Garbhprakaran, Chaukhambha Sanskrit Sansthana, Edition 10th, pg. 51.

23. Mishra Brahma Shankar, Editor Bhavprakash of Hindi Commentary, Purva Khand, Garbhprakaran, Ch. 3, Ver. 173, Chaukhambha Sanskrit Sansthana, Edition 10th, pg.53.

24. Katyayan Abhay, Editor Bhel Samhita of Vidyotini Hindi Commentary, Sutra Sthan, Ch. 16 Ver. 15, Chaukhambha Surbharti Prakashan, Edition 2017, pg. 87.

25. Sharma Purushottam, Editor Sharir Tatwa Darshnam Naam Vatadi Dosh Vigyanam, Dwitya Darshan, Ver. 20,21, Varanasi, Chaukhambha Krishna Das Academy, Edition 2009, pg. 239.

26. Sharma Purushottam, Editor Sharir Tatwa Darshnam Naam Vatadi Dosh Vigyanam, Pratham Darshan, Uttarardha, Ver. 20,21, Varanasi, Chaukhambha Krishna Das Academy, Edition 2009, pg. 220.

27. Tripathi Ravidutta, Editor Asthang Sangraha of Vaagbhatta Saroj Hindi Commentary, Sutra Sthan, Ch.20 Ver. 4, Delhi, Chaukhambha Sanskrit Partisthan, Edition 1999, pg. 375.

28. Trivedi Acharya Raghuveer Prasad, Editor Astang Sangrha of Sarvang Sundari Hindi Commentary, Sharir Sthan, Ch.6 Ver. 57, Vaidyanath Ayurveda Bhawan Pvt. Ltd., Edition 1989, pg.188.

29. Ghanekar Bhaskar Govind, Editor Vaidyakiyashubhashiasahityama, Varanasi, Chaukhambha Sanskrit Sansthan, Edition 1999

30. Tripathi Brahmanand, Editor Sharangdhara Samhita of Dipika Hindi Commentary, Purva khand Ch. 6 Ver. 13, Varanasi, Chaukhambha Sur Bharti Prakashan, Edition 2017, pg. 54.

31. Trivedi Acharya Raghuveer Prasad, Editor Asthang Sangrha of Sarvanga Sundari Hindi Commentary, Sharir Sthan, Ch.6 Ver. 76, Vaidyanath Ayurveda Bhawan Pvt. Ltd., Edition 1989, pg.191.

32. Thakaral Kewal Krishna, Editor Susruta Samhita of Dlhana Nibandha Sangraha Hindi Commentary, Sutra Sthana, Ch.35 Ver.28, Varanasi, Chaukhambha Orientaliya, Edition Reprint 2016, pg.389.

33. Kim E. Barrett, Susan M. Barman, Scott Boitano, Editor Ganong's Review of Medical Physiology, McGraw-Hill Education, Edition twenty-fifth, pg.498.

34. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Sharir Sthan, Ch. 6 Ver. 15, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg.437.

35. Pathaka Kusum Shivnath, Scientific Clinically Significant Concepts of Vayu (Vata), doi: 10.23953/cloud.ijaayush.258, Vol 6, No 1 (2017)

36. Guyton C., John E. Hall, Editor Textbook of Medical Physiology Mansfield State College, Mansfield, Pennsylvania, Eleventh edition, pg. 773.

37. Jane E. Haley, Gases as neurotransmitters, Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, U.K.

38. Martini Frederic H., Editor Fundamentals of anatomy and physiology, Prentice Hall Upper Saddle River, New Jersey, USA, Fourth Edition, pg.896.

39. Dwarkanatha C., Editor Digestion and Metabolism in Ayurveda, Varanasi, Chaukhambha Krishnadas Academy, Edition 1997, pg.53.


Journal of Ayurveda and Integrated Medical Sciences 2023;8(6)150
Tripathi R et al: Samana Vayu apropos regulation of Gastrointestinal Tract

40. Shastri Kaviraj Ambikadutta, Editor Susruta Samhita of Ayurveda Tattva Sandeepika Hindi Commentary, Sutra Sthan, Ch. 21 Ver. 14, Varanasi, Chaukhambha Sanskrit Sansthan, Edition Reprint 2013, pg.90.

41. Tripathi Brahmanand, Editor Ashtanga Hridayam of Vagbhatta Nirmala Hindi Commentary, Sutra Sthan, Ch. 12 Ver. 16, Delhi Chaukhambha Sanskrit Pratisthan, Edition Reprint 2003, pg.173.

42. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 Ver.6, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg.3.

43. Shastri Kaviraj Ambikadutta, Editor Susruta Samhita on Ayurveda Tattva Sandeepika Hindi Commentary, Sutra Sthan, Ch. 21 Ver. 12, Varanasi, Chaukhamba Sanskrit Sansthan, Edition Reprint 2013, pg.89.

44. Gupta L. P., Editor Essentials of Ayurveda, Chaukhambha Sanskrit Pratisthana, Edition 1996, pg.100.

45. Sharma R. K., Das Bhagwan, Editor Charaka Samhita of Chakrapani Dutta Ayurveda Dipika, Chikitsa Sthan, Ch. 15 Ver. 9, Varanasi, Chaukhambha Sanskrit Series Office, Edition 2018, pg. 5.

46. Kim E. Barrett, Susan M. Barman, Scott Boitano, Editor Ganong's Review of Medical Physiology, McGraw-Hill Education, Edition twenty-fifth, pg.496.

47. Shastri Pt. Kashinath, Editor Charaka Samhita of Vidyotini Hindi Commentary, Chikitsa Sthan Ch. 28 Ver. 219, 220, Varanasi, Chaukhambha Bharti Academy, Edition Reprint 2006, pg. 814.

48. Shastri Pt. Kashinath, Editor Charaka Samhita of Vidyotini Hindi Commentary, Sharir Sthan, Ch. 1, Ver. 70, Varanasi, Chaukhambha Bharti Academy, Edition Reprint 2003, pg. 818.

49. Shastri Kaviraj Ambikadutta, Editor Susruta Samhita of Ayurveda Tattva Sandeepika Hindi Commentary, Nidana Sthan, Ch. 1 Ver. 19, Varanasi, Chaukhambha Sanskrit Sansthan, Edition Reprint 2005, pg.230.



50. Pritam Moharana, Neha Rawat, Rakesh Roushan, A critical review of Apana Vayu in modern perspective www.pragatipublication.com ISSN 2249-3352 (P) 2278-0505


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