Physiology of Urine formation in Ayurveda
Dr. Vandana Verma , Assistant Professor, Department of Kriya Sharira
Faculty of Ayurveda, IMS, BHU, Varanasi
Mutra (Urine) – A liquid waste product of Ahara
Acharya Charak has explained about the mechanism of formation of Mala from the Aahar. The ingested food after complete digestion by action of Pachak pitta and Samana Vata gets separated into Prasad Bhag (Aahar rasa) which nourishes to the tissues and the Kitta bhag (waste part) which is also called as Mala. The Kitta part replenishes to the different Mal which are produced at the level of digestion and tissue metabolism like sweat, urine, faeces, tridosha, the Mal of karna, akshi, kesha, lomakoop etc. So basically the Kitta, that is formed at the level of GIT replenishes to the Mal which are form either at the level of GIT that is Mootra, Purisha and Vayu or to the Dhatu Mal which are produce during the metabolism of tissue.
Acharya Vagbhatta has described two divisions of Kitta on the basis of its consistency, Achha(liquid) and Annacha(solid). The liquid part of Kitta forms Mutra and solid part faeces.
तत्राहारप्रसादाख्यो रसः किट्टं च मलाख्यमभिनिर्वर्तते| किट्टात् स्वेदमूत्रपुरीषवातपित्तश्लेष्माणः कर्णाक्षिनासिकास्यलोमकूपप्रजननमलाः केशश्मश्रुलोमनखादयश्चावयवाः पुष्यन्ति| C.Su 28/4
तत्राहारप्रसादाख्यो रसः किट्टंचमलाख्यमभिनिर्वर्तते| प्रसादः सारः| किट्टम् असारभागः
अन्नाद्यः किट्टांशस्ततो मूत्रपुरीषे भवतो वायुश्च, Chakrapani commentary on C.Su 28/4
किट्टमपि यदेतन्नस्य पक्वस्य, तदप्यच्छानच्छभेदेन द्विधेत्याह–| तत्राच्छं किट्टमन्नस्य मूत्रं विद्याद्धनं शकृत्|| (A.Hri.Sha.3/61) यदच्छमन्नस्य किट्टं तन्मूत्रं विद्यात्| यद् घनं–संहतं, अन्नस्य किट्टं तत् शकृत्–पुरीषं, जानीयात्| (सर्वाङ्गसुन्दरी व्याख्या कृत on (A.Hri.Sha.3/61)
Structures related to Urine formation and Excretion
Vrikka (Kidney), Basti (Bladder), Mutravaha Nadi (Ureters), Mutra Prashek (Urethra)
Vrikka (Kidney): The description of kidney in relation to urine formation is not mentioned by any of the scholar of Ayurveda rather it has been mention in relation to Medavaha srotas Mula. It has been discussed as a Kosthanga and Aacharya Shushrut has described it as a site of Antarvriddhi (internal abscess).
Basti (Bladder): Basti is described as the major organ for urine formation and collection.
Mutravaha Nadi (Ureters): No direct description is found in relation to urine formation in Ayurveda. The term Gavani has been used for the ureters in Veda. However there is description of Mutravaha nadi that carry the urine from the pakwasaya upto the bladder. This is the structure which is related to the intestine and the large intestine and carries formed urine into bladder. Since ureters are retroperitoneal structure, so it might be quite possible to assume that these ducts are coming from the intestine and pouring urine into the bladder.
Mechanism of Urine Formation
Shushrut has described mechanism of urine formation in Ashmari nidana in reference to the formation of stone in the bladder. He described that ingested food digested completely by the Pachak pitta then it gets separated into the Dosha, Rasa, mutra, purish by the action pachak pitta & SamanaVata.
Mutra(urine) segregated at the level of Pakwashya (large intestine) is brought to Basti by the Mutravaha nadi continuously. For the transport of urine from pakwashya to urinary bladder by Mutravah nadi analogy of river and ocean has been given. As the river continuously drains it’s water into the ocean which act as a reservoir in the same manner urine which is formed at the level of pakvashaya from the liquid part of the Kitta is continuously drained by the Mutravaha nadi into the bladder. The ducts which carry urine are very minute, invisible, millions in numbers and have thousands of openings also and they pour their urine into bladder (Amashaya antarata). Dalhan has further explained that Amashayantrata refers to Basti(urinary bladder).
Urine formation is a continuous process which happens all through the day and night by the process of Nihsyandan (filtration). For explaining this process of filtration the analogy has been given, as an earthen pot submerged in water up to the neck, gets filled with water by the lateral pores which are present in its wall, in the same fashion the Basti gets filled with the urine by the different ducts which are coming from the intestine.
Aacharya Shushrut has described two Mutravaha Nadi and two Adhoga Dhamani (blood vessels) related to formation and transport of urine. The Mutravaha Nadi gets divided into 10 x 100 x 1000 x times’ smaller divisions are very minute, invisible, millions in numbers and have thousands of openings. This description of Mutravaha nadi could be understood as nephron, its different parts like Bowmen capsule as Sahasra mukha of Nadi and Nadi as parts of renal tubules. Whereas two Adhog Dhamani could be understood renal artery which divided and form glomerulus in Bowmen’s capsule and further it pass along with the renal tubules and make the peritubular capillaries network along with the Tubular ducts.
This whole description of Sushrut can be summarized that urine is formed by the process of filtration and is a continuous process; the thousands of minute invisible ducts carry urine from large intestine (pakvashya) into the bladder.
According to sharangdhar (Sha.Pu6/7), the Aahar gets divided into two parts i.e. Sara Bhag (nutrient part) and Asara bhaag(non-nutrient part). The liquid part of the Asara Bhag is called mutra. The water that is formed after the digestion is carried into the Basti by the different Shiras (blood vessels).
Thus there is no direct description about the Tubular structure of the nephron and the blood vessels, but the analysis of whole description shows that they are related with the urine formation and transport.
पक्वाशयगतास्तत्र नाड्यो मूत्रवहास्तु याः | तर्पयन्ति सदा मूत्रं सरितः सागरं यथा ||२१||
सूक्ष्मत्वान्नोपलभ्यन्ते मुखान्यासां सहस्रशः | नाडीभिरुपनीतस्य मूत्रस्यामाशयान्तरात् ||२२||
जाग्रतः स्वपतश्चैव स निःस्यन्देन पूर्यते | आमुखात्सलिले न्यस्तः पार्श्वेभ्यः पूर्यते नवः ||२३||
घटो यथा तथा विद्धि बस्तिर्मूत्रेण पूर्यते |२४| (S. Ni 3/21,22,23,24)
ता नाड्यो मूत्रं तर्पयन्ति विवर्धयन्तीत्यर्थः| मूत्रवाहिन्यौ मूलधमन्यौ द्वे, तच्छाखाभूता दशधा शतधा सहस्रधा च विभिद्यन्त इति दर्शयन्नाह- सूक्ष्मत्वादित्यादि| आसां नाडीनाम्| याभिरेवायं सिरास्नायुभिरावृतस्ताभिरेवायं मूत्रेण पूर्यते इति दर्शयन्नाह- नाडीभिरित्यादि| आमाशयान्तरात् आमपक्वाशयान्तरात्| स बस्तिः| निःस्यन्देन उपस्नेहेन, पूर्यते| अधोमुखत्वेन बस्तेरनूर्ध्वमुखस्यापि पूरणमुपमानेनाह-आमुखादित्यादि| न्यस्तो धृतः| विद्धि जानीहि|| Dalhan commentary (S. Ni 3/21,22,23)
Blood vessels related to the urine formation:
Shushrut has described three kind of dhamni Urdhva, Adho and Triyaka on the basis of their location in the relation to the Nabhi (umblicus) and arrangement in the body. The blood vessels located below the umbilicus which supply nutrient to lower limb and pelvic organs are called as Adhoga dhamani and they are related to the transport of flatus, urine, Shukra(semen) and Artava(menstrual flow). Total Adhoga dhamani are 30 in number. The two Adhoga dhamani (blood vessels) are related with the urine formation and help in transport of urine into the bladder.
If we observe the blood supply of ureter it is having blood supply from branches of blood vessels supplying different parts of the GIT including large intestine. Since ureter is pouring formed urine into the bladder and this may be the reason behind description that urine coming from pakwashya is carried by Mutravah nadi into bladder.
Aacharya Susruta here he explains little bit about the urine formation also in the dhamini chapter, he explains that the two Dhamnis are related with the intestine and two blood vessels helps in the digestion of food and separation of Rasa and two with formation of urine and feces. The water which is formed as a kitta in the intestine when this water comes into the Basti & collected in the Basti then this water is called as mutra before that it is called as Udaka ( S.sh.9/7).
अधोगमास्तु वातमूत्रपुरीषशुक्रार्तवादीन्यधो वहन्ति |— मूत्रबस्तिमभिप्रपन्ने मूत्रवहे द्वे I(S.Sha. 9/7)
द्वे अन्नवाहिन्यावन्त्राश्रिते नहि पित्ताशये रसमूत्रपुरीषभावेनविविच्यमानस्याहारस्यान्नभावोऽस्ति , नापि तोयस्य तोयभावना; तेन तोयमत्र भविष्यतो मूत्रस्य कारणभूतं पक्वाहारविवेकजं द्रवमयमुदकमिवोदकं , तदपि द्वे एव वहतः; तदेवोदकं बस्तिविवरप्राप्तं मूत्रमित्युच्यते, तद्वहे द्वे मूत्रबस्तिसम्बद्धे| एवमन्नमत्र भविष्यतः किट्टस्य कारणभूतं पक्वाहारविवेकजं घनमन्नमिवान्नं, तदपि द्वे एव वहतः; तदेवोण्डु(न्दु)कप्राप्तं पुरीषमित्युच्यते|| (Dalhana ccommentary on (S.Sha. 9/6-7)
Basti as a reservoir of urine and seat of Ambuvaha Srotas
Basti is situated in shroni (pelvis), is reservoir of urine and seat of Ambuvaha srotas since it is related with the body water excretion and balance . The simile of ocean and river has been given as Ocean is the reservoir of all kind of rivers in the same manner the bladder is the seat of urine or seat of ambuvaha srotas. The quantity of urine basically depends on the quantity of water intake, if the intake of water is more than more urine will be formed and if the intake is less the quantity of urine will also be decreased. Although formation of urine depends on the blood volume and the quantity of water in the plasma but it has been not described in relation to that blood volume of plasma rather it has been described in relation to the Udak. Similarly if we see the description of Udak it is 10 Anjali and is present in whole body in different forms. When this water comes into the bladder it is known as mutra & when it comes out through skin pores on exposure to the heat is called as sweat, So, these are two routes through which there is major loss of water.
बस्तिस्तु स्थूलगुदमुष्कसेवनीशुक्रमूत्रवाहिनीनां नाडी(ली)नां मध्ये मूत्रधारोऽम्बुवहानां सर्वस्रोतसामुदधिरिवापगानां प्रतिष्ठा I(C.Siddhi.9/4)
बस्तेः शरीराश्रयत्वमाहु– बस्तिस्त्वित्यादि| स्थूलगुदादिमध्यस्थितत्वप्रतिपादनेनास्य स्थूलगुदादीनां बस्त्याश्रयत्वं दर्शयति| अम्बुवहानां स्रोतसां प्रतिष्ठेति स्थानमित्यर्थः, उदधिर्यथाऽऽपगानां पूरणीयस्थानं, तथा बस्तिरप्यम्बुवहस्रोतसां विश्रामस्थानम्|आयुर्वेददीपिका व्याख्या (चक्रपाणिदत्त कृत)
Dosha involved in urine formation
The ingested food is digested completely by the Pachak Pitta and again it’s separation is done by the Pachak Pitta and Samana vata .(S.su21/10) Here the function of separation of Sara and Kitta can be understood by the formation of urine. Thus Pachaka Pitta and Samana Vata are related with the formation of urine whereas Apana Vata regulates the excretion of urine.
तच्चादृष्टहेतुकेन विशेषेण पक्वामाशयमध्यस्थं पित्तं चतुर्विधमन्नपानं पचति, विवेचयति च दोषरसमूत्रपुरीषाणि; तत्रस्थमेव चात्मशक्त्या शेषाणां पित्तस्थानानां शरीरस्य चाग्निकर्मणाऽनुग्रहं करोति I (S.Su.21/10)
विवेको रसमूत्रपुरीषाणां पृथक्करणं, समानस्य कर्म I (Dalhan commentary on S.Su.15/4)
Excretion of Urine regulated by Apana Vata
Apana Vata which is present in the lower part of the body and its site is Shroni, Basti, medra, Uru is responsible for the release of or excretion of shukra, menstrual flow, urine and foetus.
Susruta has further explained about the function of Apana Vata(S.Ni.1/19-20) that when there is urge for micturition it releases urine and in absence of urge for micturition it retains the urine into the bladder. This function could be understood as a micturition reflex and regulation of the micturition mechanism and the innervations of the bladder and the urethra.
The bladder has two kind of nerve supply i.e. sympathetic and parasympathetic. The sympathetic nerve fibers supply to the detrusor muscle and inhibit contraction of this muscle during filling and constrict the urethra and the bladder. Whereas the parasympathetic nerve fibers from the root value S2 to S4, supply to the detrusor muscle and to the sphincter muscles they cause relaxation to the muscle of the bladder neck. There is voluntary control of external sphincter of the urethra by the pudendal nerve. There is voluntary control of the micturition and the centre is situated in the pontine part of the brain and is also called as pontine micturition centre. When there is filling of bladder with certain amount of urine a stretch reflex is generated. This stretch reflex is basically a spinal reflex that causes inhibition of sympathetic nerves and there is more activation of parasympathetic nerves that produce contraction of detrusor muscle and relaxation of sphincter muscles that causes release of urine.
अपानोऽपानगः श्रोणिबस्तिमेढ्रोरुगोचरः| शुक्रार्तवशकृन्मूत्रगर्भनिष्क्रमणक्रियः|| (A.Hri.Su.11/9)
बस्तिः–मूत्राशयः| मेढ्रं–मूत्रमार्गः| गोचरो–विचरणविषयः| आयुर्वेदरसायनम् व्याख्या (A.Hri.Su.11/9)
पक्वाधानालयोऽपानः काले कर्षति चाप्यधः | समीरणः शकृन्मूत्रं शुक्रगर्भार्तवानि च ||
क्रुद्धश्च कुरुते रोगान् घोरान् बस्तिगुदाश्रयान् |I (S.Ni.1/19-20)
शुक्रमूत्रादीनां वेगकाले कर्षणमवेगकाले धारणम्, अपानस्य| (Dalhan commentary on S.Su.15/4)
Quantity of Urine
Quantity of Urine is 4 Anjali. Although there is a formation of 1.5 L of urine which do not matches with the quantity described by Ayurveda scholar but here he mentioned that its amount is not fixed, it depends on the intake of water and diet.
यत्त्वञ्जलिसङ्ख्येयं तदुपदेक्ष्यामः; तत् परं प्रमाणमभिज्ञेयं, तच्च वृद्धिह्रासयोगि, तर्क्यमेव| -चत्वारो मूत्रस्य I (C.Sha.7/15)
Functions of Mutra (Urine)
Acharya Sushrut explains that, it fills the bladder, removes excess of kleda(water) from the body, whereas the function of sweat is to retain the water.
बस्तिपूरणविक्लेदकृन्मूत्रं , स्वेदः क्लेदत्वक्सौकुमार्यकृत्; (S.Su15/5) बस्तिर्मूत्राशयः, तस्य पूरणं, विक्लेदमार्द्रत्वं च, मूत्रं करोतीत्यर्थः| अन्ये तु ‘क्लेदविवेकजं बस्तिपूरणकृन्मूत्रं’ इति पठन्ति, क्लेदविवेकजमिति क्लेद आर्द्रत्वं स चाहारस्य, तस्य विवेकात् पृथक्त्वाज्जातं मूत्रम्| केचित् ‘स्वेदः क्लेदयति’ इति पठन्ति|| Dalhana commentary on S.Su15/5
मूत्रस्य क्लेदवाहनम् | स्वेदस्य क्लेदविधृतिः–|(A.Hri.Su.11/5) सर्वाङ्गसुन्दरी व्याख्या —
मूत्रस्य क्लेदवाहनं श्रेष्ठं कर्म, मूत्रं क्लेदं निर्वाहयति| स्वेदस्य क्लेदविधारणं श्रेष्ठं कर्म, क्लेदाभावे हि शोषः स्यात्
आयुर्वेदरसायनम् —क्लेदवाहनं–क्लेदस्य बहिर्निर्गमनम्| तेन अनिलानलधारणबस्तिपूरणक्लेदधारणादीन्यन्यान्यपि कर्माणि ज्ञेयानि|
Mutrakshaya
Characteristics of Mutrakshya are oliguria, dysuria, altered colour of urine, thirst, dryness of mouth, pain in bladder or in the region of bladder, less formation and release of urine and it may be devoid of normal colour of urine or may be mixed with blood.
मूत्रक्षये बस्तितोदोऽल्पमूत्रता च; अत्रापि स्वयोनिवर्धनद्रव्योपयोगः | (S.Su.15/11)
मूत्रेऽल्पं मूत्रयेत्कृच्छ्राद्विवर्णं सास्रमेव वा| (A.Hri.Su. 11/22) सर्वाङ्गसुन्दरी व्याख्या —मूत्रे क्षीणेऽल्पं मूत्रयेत्, कृच्छ्राद्विवर्णं सरक्तमेव वा|
आयुर्वेदरसायनम् व्याख्या– अल्पं मूत्रं कृच्छ्रान्मूत्रयेत्| तच्च विवर्णं-रक्तमिश्रवर्णाभं, रक्तमिश्रमेव वा| एवकारेण रक्तवर्णाभासत्वं व्यावर्त्यते| अत एव विवर्णशब्देन तल्लभ्यते|
मूत्रक्षये मूत्रकृच्छ्रं मूत्रवैवर्ण्यमेव च| पिपासा बाधते चास्य मुखं च परिशुष्यति|| (C.Su. 17/71)
Mutravriddhi
Polyuria, increased frequency of urine, distension of bladder, pain in bladder.
मूत्रं तु बस्तिनिस्तोदं कृतेऽप्यकृतसंज्ञताम्||(A.Hri.Su. 11/13)
मूत्रं वृद्धं बस्तेर्निस्तोदं–अतिव्यथां कुर्यात्| तथा कृतेऽपि मूत्रेऽकृतसंज्ञतां–अकृताभासत्वमिव कुर्यात्| सर्वाङ्गसुन्दरी व्याख्या
मूत्रं मूत्रवृद्धिं मुहुर्मुहुः प्रवृत्तिं बस्तितोदमाध्मानं च I (S.Su.15/11) आध्मानमिह बस्तेरेव|| Dalhana
Clinical conditions related to Urinary system (Mutravaha Srotas)
When there is vitiation of mutravaha srotas functional derangement will be observed in urine formation and release. There will be excess or less frequency and quantity of urine for urine release and release may be associated with pain.
मूत्रवहानां स्रोतसां बस्तिर्मूलं वङ्क्षणौ च, प्रदुष्टानां तु खल्वेषामिदं विशेषविज्ञानं भवति; तद्यथा- अतिसृष्टमतिबद्धं प्रकुपितमल्पाल्पमभीक्ष्णं वा बहलं सशूलं मूत्रयन्तं दृष्ट्वा मूत्रवहान्यस्य स्रोतांसि प्रदुष्टानीति विद्यात्| (C.Vi. 5/8)
तत्र विद्धस्यानद्धबस्तिता मूत्रनिरोधः स्तब्धमेढ्रता च (S.Sha.9/12)
Summary of urine formation and excretion
Digestion of ingested food by the action Pachaka Pitta and Saman Vata and separation into Saar bhaag which provides nourishment to tissues and Kitta bhaga (waste part) in large intestine, from Liquid part mutra and from solid part feces is formed.
The mechanism of urine formation is Nihsyandan(filtration) and it happens whole day and night means it is continuous process. The formed urine is carried by two mutravaha Dahmni/ nadi from Pakwashya(large intestine) into Basti (urinary bladder). Excretion of urine is regulated by Apana Vata.
Physiological and Clinical significance of Basti (Bladder) and Vrikka (Kidney)
Vrikka is not described in relation to urine formation. It is moola of Medovaha srotomula, related with fat metabolism and seat of Antarvridhi (internal abscess). Basti is a marma.
It is organ related to urine formation & it regulates the water content in body since it is seat of Ambuvaha srotas.
Bladder is the site of stone formation it is site for Uttar Basti chikitsa(a kind of panchakarma procedure for alleviation of Vata dosha).
Characteristics of injury to the bladder
Retention of urine, feces and flatus, pain in groin and bladder, distension and stiffness in umbilical and pelvic region.
बस्तौ तु वातमूत्रवर्चोनिग्रहवङ्क्षणमेहनबस्तिशूलकुण्डलोदावर्त गुल्मानिलाष्ठीलोपस्तम्भ नाभिकुक्षिगुदश्रोणिग्रहादयःवाताद्युपसृष्टानां त्वेषां लिङ्गानि चिकित्सिते सक्रियाविधीन्युक्तानि|| (C.Siddhi 9/6)
Assessment: Multiple Choice Questions
Q.1. What is Anjali praman of Mutra :
- 4 Anjali
- 2Anjali
- 6 Anjali
- None
Q.2.Which dosha help in formation of urine:
- Samana Vata
- Pachak Pitta
- Both 1 & 2
- None
Q.3.Which statement is not true about Basti:
- It is counted as Marma
- It is Moola of ambuvaha srotas
- It is called as Pranayatan
- None
Q.4. Which statement is true about the Apana Vata:
- It causes release of Urine on micturition urge
- It retains urine in bladder
- Both
- None
Q.5. What is characteristic of Mutrakshya:
- Dysuria
- Passing of Rakta in urine
- Both 1 &2
- None
Q.6. What is characteristic of Mutravriddhi:
- Increased frequency and quantity of urine
- Heaviness and Pain in bladder
- Both 1 &2
- None
Q.7. What is characteristic of Mutravaha srotodushti :
- Increased frequency of urine
- Decreased frequency of urine
- Both 1 & 2
- None
Q.8. What is characteristics of injury of the bladder
- Retention of urine
- Retention of feces and flatus
- Both 1 & 2
- None
Q.9 What is function of Mutra…
- Filling of bladder
- Removes extra water from the body
- Both 1 &2
- None
Q.10 Which kind of dhamani is related to urine formation:
- Urdhva dhamani
- Adhog dhamani
- Both
- None
Answer sheet for MCQ
| Question no | Answer | Question no | Answer |
| 1 | 1 | 6 | 3 |
| 2 | 3 | 7 | 3 |
| 3 | 4 | 8 | 3 |
| 4 | 3 | 9 | 3 |
| 5 | 3 | 10 | 2 |
