Review of Structural and Functional Anatomy of Kidney in Ayurvedic Literature with Special Reference to Diseases of the Kidney

1. Professor, Department of Swasthavritta, A.S.S Ayurved College, Nashik, Maharashtra, India. 2. Associate Professor, Department of Rasashastra and Bhaishajya Kalpana, A.S.S. Ayurved College, Nashik, Maharashtra, India.

Abstract

Description of organs and their treatment in Ayurvedic texts is very brief. In today’s world when the diseases of organs like kidneys, heart, liver, and brain etc., are becoming very common, Ayurvedic practitioners find these descriptions inadequate to treat patients with such diseases. An effort was made to assess whether critical analysis of references related to kidneys in classical Ayurvedic texts provide inputs to an Ayurvedic Practitioner to understand the pathogenesis of Chronic Kidney Disease (CKD). Tantrayukti based interpretation of references of kidneys in classical Ayurvedic texts establishes that kidneys were known to, and are elaborately described in Ayurveda, with their anatomical details such as embryological origin, name, number, relation with other abdominal organs, location etc. They are known by the name of Vrukka, which are the abdominal organs that are two in number and are described as Basti Marma (which includes the kidneys, ureter, and Bladder) for the purpose of diagnosis, prognosis, and treatment of all urine related diseases. Basti Marma is one of the three Maha Marmas i.e., most important vital organs of the body viz., Shiro (~brain), Hridaya (~heart) and Basti (~bladders). Vrukka (kidney) is formed from the nutritious part of Kapha, Meda and Rakta, gives the inputs to the practitioner to consider the metabolism of these factors in diagnosis and treatment of CKD. Physiology of formation of urine is also elaborately described in Ayurveda. The reference of Sushruta which discusses about Sahastrshaha Sukshma mukhani (~ thousands of minute openings invisible to naked eye) where urine is formed resembles the description of glomerular filtration. Formation and processing by Samaana, role of Jathar Agni, Dhatvagni and Bhutagni in formation of Mutra (~urine), storage and excretion at the level of Bladder, by Apaana is defined clearly, and this description is of immense value for practitioners. Relation of Basti Marma to Kleda (~body fluids) and its pathological connection with specific diseases is also evident. Understanding of various factors viz., Kleda (~body fluids), Marma (~vital organs), Prana (~life force), Oja (~vitality), Kalaa (~Internal membranes) Jathar Agni, Dhatvagni, Bhutagni etc., and their role in pathogenesis of CKD provides Vaidyas with inputs to devise the line of treatment of patients suffering from CKD, taking into consideration the individual condition of each patient.

Basti, Marma, Vrukka

Currently, there is tremendous rise in the number of patients suffering from diseases of organs viz., Chronic Kidney Disease (CKD), ischaemic heart disease, diseases of the brain etc., (1),(2),(3),(4). Description of structure and functions of organs is perceived to be very brief in classical Ayurvedic texts. Students of Ayurveda find it difficult to fully comprehend the structure and their functions, which form the basis of diagnosis and treatment of such diseases in absence of elaborate description of these organs. Tantrayukti (~ Ayurvedic methodology of interpretation of the verses) is an important scientific tool described in Ayurveda to extract unlimited information from limited references. Here, we have demonstrated how we can derive essential information about the structure and function of kidneys from classical Ayurvedic texts using Tantrayukti. Previously we have published a study on the Ayurvedic principles for diagnosis and treatment of CKD and here we intend to describe the structural and functional aspects of kidney (5).

Methodology: Compilation of references related to kidneys and the urinary system from the Samhitas (~Classical Ayurvedic texts), that are scattered all over the texts was done. Collected references were indexed as per the logical sequence of information in such a way that it would provide the required information for a treating doctor about anatomy and physiology, and to assess whether it throws some light on the new aspects, regarding structure and functioning of kidneys. These references were used as the material for this research.

These references were interpreted on the basis of Tantrayukti, which is a tool described in Ayurveda to scientifically derive information from the textual quotes, as the standard guideline for interpretation of these quotes.

Uhya Tantrayukti to Unleash the Knowledge Hidden in Concise Sutras

References in Ayurvedic texts regarding kidneys, their functions, diseases etc., are very few. If we try to analyse the information with a standard approach it will not yield sufficient information that can be used for diagnosis and treatment of complex diseases like CKD. For this purpose, the use of “Uhya” Tantrayukti is recommended. Charaka states that it helps to derive the exact meaning of the text. Tantrayukti guides us to the exact meaning like a light in the dark (6).

Uhya Tantrayukti is used in conditions like these when the references are very few. This helps in getting unlimited information from limited references (7) and derives the information. A detailed analysis (collection, elaboration and expansion) of the following textual references regarding kidney was done using this methodology to understand the applied anatomy, physiology, pathogenesis etc., of CKD from the references scattered across the texts.

References of Kidney in Ayurvedic Literature

Detailed search of Ayurvedic texts (Samhitas) revealed that the detailed description of kidneys was known to Ayurvedic Acharyas along with their anatomy and physiology. The following reference of Charaka Samhita lists the abdominal organs in human body. Kidneys are called by the name of Vrukka in Ayurveda. In this reference Vrukka are described as one of the 15 Koshthangani (~abdominal organs) (8). These abdominal organs are Nabhi (~umbilicus), Hriday (~heart), Kloma (~pancreas), Yakrut (~liver), Pleeha (~spleen), Vrukkau (~two kidneys), Basti (~bladder), Purishadhara (~caecum), Amashaya (~gastrum), Pakwashaya (~part of large intestine), Uttara guda (~upper part of anus), Adhara guda (~lower part of anus), Kshudrantra (~small intestine), Sthulantra (~large intestine), Vapavahanam (~omentum).

There is mention of Basti (bladder) separately in the same reference along with Vrukka. Based on this, it was interpreted that Ayurvedic Acharyas were very clear that these two are separate entities. The dictionary meaning of Vrukka is kidney (9), also the word “Vrukkau” is used to describe them, which according to Sanskrit grammar is a dual form that means two Vrukkas. It is described as an abdominal organ. There is no other organ in the abdomen, which is two in number, apart from kidney. Hence, it can be clearly said that Vrukka refers to kidneys.

Secondly, if the reference is examined in detail, it will be known that the organs are described in groups like Yakrut and Pleeha (liver and spleen), Uttara guda and Adhara guda, Amashaya and Pakvashaya, Kshudrantra and Sthulantra and Vrukka and Basti. Basti here is explained as Mutrashaya i.e., reservoir of Urine which means bladder and the two organs connected to Basti can be none other than kidneys (6).

This inference is drawn based on “Vidhana” Tantrayukti described by Charak in siddhi sthana. Vidhan Tantrayukti specifies that there is a sequence and pattern to the information described in a stanza and is repeated and applied to other stanzas in the other part of the chapter (6).

Not only Sushruta, but Charaka also has used the word Vrukka for kidneys and he also has used the dual form suggesting two kidneys.

This reference is regarding the sites of abscesses that are formed internally. It says that when toxins enter the Rakta (~blood) and Mamsa (~muscles), the site of these organs is gambhira (~deep)and the condition thus generated is very daruna (~serious). There is description of organs where these abscesses are formed viz., Hriday, Kloma, Yakrut, Pleeha, Vrukkayoho (two kidneys), Nabhi (umbilicus), Vankshan (~groins) and Basti (10). Here, also there is separate mention of kidneys (Vrukka) and bladder (Basti) and dual form of the word Vrukka suggesting two in number is used. However, the word is not commonly used for kidneys elsewhere.

Embryological Formation of Kidney

Acharya Sushruta has even described the formation of kidney in the embryo. It says that Vrukka are formed from the Sara (the purest form) of blood (Rakta), lipids (Meda) and Kapha (11). According to Ayurveda, the process of Sara-kittavibhajan (separation of nutritious part and excretory part) happens at the level of intestines by Jathar Agni (~digestive fire) (12) and also in the Dhatus (~tissues) by Dhatvagni (~factor responsible for metabolism of respective tissues) (12).

The Sara-kittavibhajan happens since the life in the womb and is continued till last breath. Acharya Sushruta has mentioned that the kidneys are formed from the metabolism of Kapha dosha and Dhatus (~ tissues), like Rakta (~blood) and Meda (~lipids). Metabolism is a continuous process in the body till the end of life. Any disruption in the metabolism of these dhatus and doshas is likely to adversely affect the functioning of these kidneys. Vaidyas must consider this process of Sara-kittavibhajan, which is reliant on the role of Agni and Dhatvagni in light of this reference, while treating patients of CKD.

In addition to kidneys, it also describes the formation of Basti i.e., bladder in this case. The purest form of Rakta, Kapha, is further transformed by Pitta in a different state and Vayu creates the space in these structures to form intestines, Guda (~anus) and Basti in the body, which means Basti here is referred as a reservoir along with other similar structures like intestines and anus (11). Formation of bladder and kidney in the embryo is not the same and hence it is stated differently.

Charaka has also listed the formation of organs in the foetus from Matruja Bhava (~from the maternal parts of the genetic material). It says that, Twak (skin), Rakta (blood), Mamsa (muscles), Meda (lipids), Nabhi (umbilicus), Hriday (heart), Kloma (pancreas), Yakrut (liver), Pleeha (spleen), Vrukkau (two kidneys), Basti (bladder), Purishadhara (caecum), Amashaya (gastrum), Pakwashaya (part of large intestine), Uttara guda (upper part of anus), Adhara guda (lower part of anus), Kshudrantra (small intestine), Sthulantra (large intestine), Vapa and Vapavahanam (omentum) are all created predominantly from the maternal part of genes (13).

While describing Vrukka, Dalhan the commentrator of Sushruta Samhita explains what Sushruta means by Vrukka and their location. Mamsa pinda dwayam (~two muscular) structures Ekovama parshva stitaha (~one situated on the left lateral side) and dwitiyo dakshin parshva sthithiha (~other at the right lateral side).

These references show that kidneys were known to Ayurvedic Acharyas with their anatomical details such as embryological origin, name, number, relation with other abdominal organs, location etc.

The term Basti is used several times in Ayurvedic texts in different contexts at different places. This creates lot of confusion in its interpretation especially while discussing Mutraghata (~anuria) and other diseases of the urinary system.

After careful analysis of most of the references, it was observed that the term Basti is used mainly with three meanings:

i. Basti-Marma (~vital organ)

ii. Basti-Mutrashaya (~bladder)

iii. Basti-One of the five main Panchakarma procedures

Ashtanga Sangraha further clears the confusion arising for the use of Basti in different contexts.

This description says that Basti described in chapter of Marma is the seat of all diseases related to urinary system. Here, Basti is used as alternative word for Vrukka i.e., kidneys. In this reference it seems that the term Basti Marma is used collectively for kidney, ureters and bladder. It says that Basti is like a pot turned upside down which is filled laterally with the fluid called urine formed in thousands of minute openings and collected by ureters (14).

It says that Basti is the seat of all diseases related to urinary system. It is described in the chapter of Marma.

It clearly implies that the word Basti used here refers to Basti Marma. This is derived based on “Adhikaran” Tantrayukti, which says that the meaning of the word must be inferred after considering the context in which it is described. It says that Adhikaran is the subject or the context that has been kept in mind by the author while describing a subject (7).

Hence, it clearly implies that the word Basti used here refers to Basti Marma. It also says that it looks like a pot turned upside down, which is filled with a fluid called urine that is formed from thousands of small openings. Through these same openings the dosha’s and the diseases also enter the urinary system or set of organs. This description matches with the description of kidneys, ureters, and bladder. There is a mention of thousands of minute openings in which urine is formed, this can be easily interpreted as nephrons (15). This shows that the structure of nephrons and glomerular filtration was also known to and described by Ayurvedic texts.

Location of Kidney

In the chapter of Marma while describing Basti Marma, Charaka says that ‘Basti’ is situated in between Sthulaguda (~part of large intestine), Mushka (~testes), Sivani (~junction of two testes), Shukravahanadi (~vas deferens), Mutravahanadinam (ureters) madhye (16). It is also referred to as the end point of fluid metabolism comparing it to the ocean to which all the water channels ultimately meet. Udadhi means ocean and Apaga means water channels, Pratishtha here means end point (9).

Ashtanga Sangrah describes Basti as a structure which is curved like a bow having one opening (17). This bow like curve refers to the outer curvature of kidney and one opening refers to the opening of ureter. Whereas Basti as Mutrashaya is described as pot turned upside down. In the lower back of the abdomen Basti Marma is a bow like structure having one opening.

Another reference of Sushruta clearly describes the location of kidneys and its relation to other organs in an elaborate manner. It says that Basti is situated between these structures Nabhi (umbilicus), Prushtha (~back), Kati (~lower back), Mushka (~testis), Guda, Vankshan and Shefas (~penis) (15).

This reference explicitly says that Basti (~kidney), Basti Shira (~bladder), Paurusha (~penis), Vrushanau (~two testes) are directly connected to each other and are situated in the Gudasthivivar (~pelvis) and are kept hanging in the place by Sira (~vessels) and Snayu (~ligaments) like a Alabu (bottle gourd) on the plant (15).

If we view these references along with the description by Dalhana, that the Vrukka are located on two lateral sides in the lower abdomen (Kukshi), we get a clear picture of the Basti Marma i.e., kidneys.

These references indicate that the location of Basti is between large intestine and ureters, and that whole urinary system is called Basti Marma. The description of curved shape from back side and having one opening is suggestive of kidney. However, the term adhomukho i.e., having opening to the lower side refers more to bladder. The use of dwivachana (dual form) in the commentary and saying that when both the Basti are injured the death is sure and immediate, also suggest kidney.

Marma is another anatomical feature described exclusively by Ayurvedic texts which means vital points in the body. The precision in description of these Marmas is that they have described minute details of these Marmas i.e., their number (107), exact location, measurement, and composition (Mamsa, Sira, Asthi, Sandhi etc.,). These Marmas are so vital that damage to it can be fatal and even slight damage to these, can lead to serious diseases (16).

Basti Marma is one of the three most important Marma, due to its importance and it is referred as Mahamarma. This description of three Maha Marmas correlates with the description of Shiro (brain) Hriday (heart) and Basti (kidney) and we all know how important these organs are for the continuation of life (16).

However, this correlation is not merely for theoretical purpose, the fact that kidney can be related to Basti Marma opens completely new areas for diagnosis, prognosis, and treatment options for diseases of kidney. It also gives a clear understanding of the kidneys in Ayurveda and helps to formulate the line of treatment of such diseases.

Marma, specifically the three Maha Marmas (the major vital organs) are the seat of Prana, the life force (16) and since Basti-Marma is one of the three major Marmas in the body, it is obvious that existence of our life is grossly dependant on Basti Marma i.e., kidney.

It has been stated that the Pranas are located in these three Maha Marmas. Hence, one should always try to protect them. The protection plan for Maha Marmas is described as having three aspects one is prevention of damage (external injury and internal damage), second is following the recommended lifestyle (Diet, Dinacharya and Rutucharya etc.,) and third is attending to the complaints of these Marmas immediately (16). It also means that we must think of Prana as a factor in the treatment of diseases of kidney.

Prana is directly connected to Oja since it is related to life. It is said in the references that if Oja is damaged the life is at threat (18) and it is also evident from this reference that Oja and Prana are in conjunction with each other, which means wherever Prana is present Oja is also present and vice versa (19).

Sushruta also has elaborately described the applied anatomy of Basti and other allied organs while describing Ashmari (~renal calculi) in the same way, along with the famous description of formation of urine (applied Physiology). He has mentioned Basti and Mutrashaya in the same verse suggesting Basti as Basti Marma which he says is Pranayatana (seat of Prana) and Mutashaya as bladder (15). This is confirmed by Dalhana in the description of Basti Marma (20).

If the references are viewed along with the description by Dalhana, that the Vrukka are located on two lateral sides in the lower abdomen (Kukshi), a clear picture of the Basti Marma i.e., kidneys is evident.

Description of Physiology of Kidney in Ayurveda

Ayurvedic texts have elaborately described the process of formation of urine. It is comparable with process of glomerular filtration described by modern medicine (15). Additionally, it gives importance to the role of Agni in the formation of urine at initial stages.

The meaning of the stanza is as follows:

• The ureters in Pakvashaya fill the urine continuously like the rivers pouring in the ocean.
• Urine is generated in the Amashaya through thousands of openings which cannot be seen with naked eye because they are extremely minute.
• This process is going on continuously day and night while being awake or in sleep. Urine is filled drop by drop from two lateral sides in the Basti which looks like a pot turned upside down.

The Acharyas say that asamsahastrashahamukhani (~ the thousands of openings) are not visible by the naked eye as they are Sukshma (~very small). This description is quite like the description of glomerular filtration at the nephrons which separate urine from blood. It is evident that Ayurvedic Acharyas are aware of nephrons as the basic generating units of urine, all this description must be viewed in light of the fact that there was no microscope, or any other machine which may help to visualise it. Ashtanga Sangraha and Sushruta, both have described it in exactly the same way (11),(15).

The mention of Amashaya (~proximal part of alimentary canal), the seat of Agni, in the process of formation of urine is something unique described in Ayurvedic texts. This reference is therapeutically very important. Acharya Dalhana, the commentrator of Sushruta Samhita has elaborately dwelled upon the role of Amashaya in the formation of urine. To understand it in the context of modern medicine we can consider it as an intestinal factor in the formation of urine (explained as Purishdhara/Maladhara kalaa) like the intestinal factor in the formation of blood. Acharya Dalhana has also discussed the extent of area that the Purishdhara/Maladhara kalaa covers (20).

Stools and urine are collectively referred to as Mala (~metabolic waste products) in Ayurveda and are formed from digestion of the food (12). This process is called as Sara-kittavibhajan, which means separation of Sara (~nutritious part) and Kitta (~excretory part) from the food that is digested. Kitta is the synonym of mala. The etymology of the word (Mala) in Sanskrit specifies the exact meaning. Malinikaranatmalaha means mala which, if retained in the body causes serious toxic build up in the body.

Jathar Agni (~main digestive fire) is the most important factor responsible for this, Sara-kittavibhajan i.e., primary or first level of separation. The solid form of Mala is Purisha or faecal matter, which excretes the non-water-soluble part whereas the liquid part is called as Mutra or urine, which excretes the water-soluble part of metabolic waste that is generated (12).

Another reference of Sushruta says that the process of formation of urine starts in Purishadhara kalaa (~membrane which carries out the function of separation of nutrients and excretory products) in the intestine. They have even described the area covered by Purishadhara kalaa which is also called as Maladhara kalaa (20). In the context of formation of urine, the membrane where separation of Rasa and Mala happens, is called as Purishadhara kalaa. It is the fifth one, which is situated in the Pakvashaya (~distal part of alimentary canal). It separates the Mala into mutra (urine) and Purisha (~faecal matter) in the intestine. It is spread over in the abdomen in the periphery of liver, covering intestines till caecum and rectum. This is the second level of separation occurring at the level of glomerular filtration.

Since Kalaa is like a membrane between the tissue and the cavity entitled with separation of urine, part of Maladhara kalaa pertaining to urine generation, described in Ayurvedic texts, may refer to structure of glomerulus, which is open for discussion (11),(20).

Kalaa written as in Devanagari script is a very typical anatomical structure described in Ayurveda Sharir. In Ayurvedic texts Twacha (~ skin) is described as an external covering and Kalaa as an internal lining. It can be translated as a membrane, in Ayurvedic texts it is defined as separation between the tissues and the cavity (11).

On looking at the detailed description of the Kalaas, it will be evident that they are placed at strategic locations where lots of metabolic, transformational and transport related activities are happening e.g., liver-spleen, muscle tissue, blood vessels, intestines, omentum, bone marrow, internal spaces of joints etc. In the context of this description of Kalaa, the uterus, and its connection with Rasa-rakta is also mentioned.

The process of formation and storage of urine are described separately. This is evident from the fact that these functions are assigned to two different types of Vayu viz., Samaana and Apaana, Samaana-responsible for separation of Rasa, urine and stool from the process of digestion of food i.e., for formation of urine and Apaana- responsible for storage (when the urge of urine is not there) and excretion of urine (when there is urge of urination) (21).

Samaana is traditionally known to be helping in kindling the digestive fire, but detailed analysis of the textual references throws up new dimension of functions of Samaana, it not only facilitates the functions of Jathar Agni i.e., the main digestive fire but also facilitates the function of dhatvagni i.e., the metabolism at tissue level and Bhutagni the metabolism at the level of five basic elements. This inference can be drawn based on following reference of Charaka Samhita.

According to Charaka Samhita, the area of operation of Samana extends up to Swedavaha srotas i.e., channels of sweat which means originating from lipid tissue and extending up to pores of skin, Ambuvaha srotas i.e., all fluid channels and all fluids in the body and also the Doshavaha srotas which extends up to each and every cell of the body (22) as Doshas are omnipresent according to Ayurveda. This means the area of operation of Samana Vayu is whole body. It regulates the core body temperature and heat metabolism of the body with Agni which is also known as Ushma. The most important fact is that it regulates the balance of heat and water in the body and hence plays an important role in the formation of urine and sweat from the food in the digestion process (23).

Samanaa type of Vayu is assigned the job of second level of separation which happens at the level of Dhatvagni i.e., tissue level. The third level of separation happens at the level of kidneys which is evident from the description of formation of urine described by Sushruta Samhita (15). The formation of urine according to Ayurveda starts in Pakwashaya, part of large intestine and is taken forward in Basti Marma i.e., kidneys, large intestine is connected to Basti Marma by way of Adhoga Dhamani (23).

The purpose of urine according to Ayurvedic texts is to process the fluids in the body along with the liquid part of excretory products (excrete the water-soluble metabolic wastes) (24).

This reference if read in connection with other reference which says that urine is formed in the Basti Marma by thousands of minute openings makes it crystal clear that it was known to Ayurvedic experts that urine is generated through glomerular filtration and the metabolic soluble waste products need to be excreted out failing which can create serious disease conditions.

Kleda or body fluids are another important concept of Ayurveda that is useful to understand the pathophysiology of CKD. The extent and meaning of Kleda and its normal quantity in a healthy body has been elaborately explained by Charaka Samhita. The concept of Kleda encompasses the fluids that are taken away in loose motions, urine, watery content of blood, the moistness of the skin, the serous discharge from the wounds, sweat etc., (8).

This Kleda is connected to the Basti Marma as is clearly described in the following reference (16) as endpoint of fluids. Since Kleda encompasses all fluids in all tissues of the body it is very rightly considered as an important factor in the pathogenesis of many diseases like Udara (~ascites), Shotha (~oedema), Madhumeha (~diabetes), Mutravikar (~diseases of urinary system) etc.

Hence, for a practising Vaidya, it is important to note that formation of Mutra (~urine) happens at three levels; first at the level of Jathar Agni, in Amashaya. Second at the level of Purishadhara kalaa in Pakwashaya and at the level of Dhatvagni by Samaana Vayu, because to carry out all the metabolic excretory products is the role of Mutra, which is spread all over the Dhatus and third at the level of Basti Marma i.e., kidneys by Bhutagni particularly Apya Agni. A Vaidya can ascertain the level at which there is disruption of formation of urine and treat accordingly.

From the above references it may be said that physiology of formation of urine is elaborately described in Ayurveda including formation, processing, storage, and excretion defined clearly. It’s relation to Kleda and its pathological connection with specific diseases is also evident from the above references.

Summary and Observations

All these references show that:

1. Kidneys were known to Ayurvedic Acharyas with their anatomical details such as embryological origin, name, number and their relationship with other abdominal organs, location etc.

2. Kidneys were known as Vrukka and bladder was referred to as Basti. Kidney and bladder are described separately as abdominal organs connected to each other where kidneys are two in number and bladder as one.

3. The bladder is described like a pot turned upside down filled from the sides. Whereas kidney is described as structure having single opening and curved bow like structure.

4. Embryological formation of kidneys are from Rakta, Kapha and Meda, whereas bladder, intestines, and Anus are formed from Rakta and Kapha by Pitta and Vayu.

5. The fact that embryological formation of kidneys and bladder described in Ayurveda is different emphasises that it was known to Ayurveda that the structure and function of these two entities is altogether different.

6. The term Basti is used in various contexts, in the context of Marma it refers primarily to kidneys and collectively to kidneys, ureter and bladder.

7. It can be interpreted that Basti Marma refers to kidney. Brain (Shiro), heart (Hriday) and kidney (Basti), are the three vital organs of the body, referred to as Maha Marmas of the body.

8. The main function of urine according to Ayurveda is to excrete the processed fluids (metabolic waste products in liquid form) i.e., Kleda of the body. This Kleda is spread all over the body and encompasses all fluids in all the tissues. Basti Marma i.e., kidneys are the end point of all fluid metabolism in the body.

9. Hence, urine is connected to Basti Marma and urine formation is the main function of Vrukka/Basti Marma.

10. The structure of nephrons and glomerular filtration was also known to and described by Ayurvedic texts.

11. Formation of urine at the first level is done by separation by Jathar Agni in the intestines, at the second level by Samana Vayu in the Purishdhara kalaa in the intestines and the third level by Aapya Bhutagni at the Maladhara kalaa in the Basti Marma (glomerular filtration).

12. Maladhara kalaa also called as Purishdhara kalaa is a membrane, that does the function of separation/filtration of urine and is spread in liver, intestines, and kidney.

13. Area of operation of Samana Vayu is whole body and it is connected to sweat glands, all fluids, and Agni. It regulates the core body temperature and helps in maintaining fluid balance and hence is connected to intestines and kidneys.

Discussion

Kidneys were known as Vrukka, their structure i.e., anatomical details such as embryological origin, name, number, relation with other abdominal organs, location etc., is elaborately mentioned. It gives important inputs to the practising Vaidya so as to understand the pathogenesis of CKD.

Since kidneys are identified as Maha Marma, it is seat of Prana (~ the life force) and Oja (~vitality). The methodology of treating diseases of Marma and of Oja are described in Ayurvedic texts. Those can be used as guidelines for devising the line of treatment.

Description of embryological formation of kidneys from Rakta, Meda and Kapha is an important guideline for a practicing Vaidya to look for disruption in the metabolism of these factors as a clue to understand the pathogenesis of CKD.

Kidneys through Basti Marma are an end point of all fluid metabolism in the body. All fluids are denoted by Kleda, the function of Mutra is to carry out the excess Kleda in the body. Metabolism cannot happen without Agni; hence it is the seat of Aapya Agni one of five Bhutagni.

Jathar Agni, Dhatvagni and Bhutagni all are involved in the formation of urine according to Ayurveda. Samaana Vayu is connected to formation of urine and Apaana Vayu is connected to storage and excretion of urine.

Conclusion

Structural and functional anatomy of kidney revealed from critical analysis of description related to kidney in classical Ayurvedic texts provide vital information for a practising vaidya. This description illustrates that the physicians of the past era had in depth knowledge of the renal system.

Disclaimer: This paper is being published to highlight the ancient understanding of human anatomy and physiology. However, readers are cautioned that the medicine has evolved with better methods of investigation and more evolved understanding.

DOI and Others

DOI: 10.7860/JCDR/2024/67000.19333

Date of Submission: Aug 14, 2023
Date of Peer Review: Nov 29, 2023
Date of Acceptance: Mar 01, 2024
Date of Publishing: Apr 01, 2024

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. No

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