Strotas are the pathways within the human body which communicates and links the different corners. These pathways helps in manufacture and transportation of essential ingredients which support the life entity, the basic amenities needed to manufacture and create the tissues of the body and to flush out the unnecessary things which contaminate the inner sanctum. The pathways, the sterility and healthy existence and proper functioning of which defines our existence, health and immunity status. The pathways when gets blocked, chocked, clogged or contaminated leads to serious damages, diseases and also death. Ayurveda was the first medical system to announce and describe the existence of millions of pathways within the human body. They called these ducts or channels or tubular or transportation systems of the body as ‘Srotas’.
Definition – Strotas
स्रवणात् स्रोतांसि ||
(च. सू. ३०/१२)
स्रवणादिति रसादेरेव पोष्यस्य स्रवणात् |
Those from which Sravana or flow of body substances take place or those through which the materials flow in the body are called Srotases. Srotases are the channels of the body through which the materials needed for tissue building, nutrition and other nutrients flow from one corner of the body to the other. We can tell that the materials are transported through the channels from the place of production to place of need.
According to Chakrapani, the commentator of Charaka Samhita, the channels which transport the Poshaka dhatus (the part of the rasa etc tissues which flow to provide nutrition to the successive tissues) are called Srotas.
Dhatus or tissues are of 7 types according to Ayurveda. They are:
- Rasa (Lymph, plasma or serum)
- Rakta (blood cells)
- Mamsa (muscles or flesh)
- Meda (fat)
- Asthi (bone)
- Majja (bone marrow)
- Shukra (semen)
All these tissues are a product of Ahara rasa or nutrient essence of food. The first step is the proper digestion of food in the stomach and intestines. This process results in the creation of the essence of the food, known as Ahara Rasa or Poshaka Rasa Dhatu. After its formation, this initial tissue is circulated throughout the body via the heart to provide nutrition to all the other tissues, or dhatus. Each dhatu has a dhatvagni or tissue fire. In Ayurveda, it is believed that cells take the necessary materials or portions from the nutrient juices or essence of food during circulation based on the law of selective absorption.
This process ensures that the body maintains a state of balance and optimal health. Tissue fire of Rasa dhatu, Rasa Dhatwagni acts on the nutritive Rasa and breaks it into Poshya or sthayi rasa dhatu (the rasa dhatu proper). Thus the Poshaka (that which provides nutrition) rasa gets converted into Poshya or sthayi rasa (that which is nourished). The sthayi rasa dhatu nourishes the rasa dhatu components all over the body.
Structure of Strotas
मूलात् खादन्तरं देहे प्रसृतं त्वभिवाहि यत् |
स्त्रोतस्तदिति विज्ञेयं सिराधमनिवर्जितम् ||
(च. सू. ९/१३)
Srotases distribute from the root to any terminal portion of the structure or body. They are located within the spaces of the body, spread all through the body, and carry essential materials. They are totally different structures from Siras (veins, lymphatics etc) and dhamanis (arteries, nerves).
स्वधातुसमवर्णानि वृत्तस्थूलान्यणूनि च|
स्रोतांसि दीर्घाण्याकृत्या प्रतानसदृशानि च||
(च. वि. ५/२५)
The srotas has the color of the dhatu (tissue) that they are carrying or transporting. They are of different shapes and sizes viz, round, thick, large, small, microscopic, elongated and form network and branches. One can consider every cell as a srotas since transportation occurs within and between the cells.
यावन्तः पुरुषे मूर्तिमन्तो भावविशेषास्तावन्त एवास्मिन् स्रोतसां प्रकारविशेषाः|
(च. वि. ५/३)
Additionally, while describing the varieties of Srotas, Charaka specifies that the number and types of Srotas in the body correspond to the number of solid structures present.
Synonyms of Strotas
Synonyms– Srotaamsi, siraa, dhamanyaha, rasaayanyaha, rasa vaahinyaha, naadyaha, panthaanaha, maargaaha, shareera chidraani, samvruta asamvrutaani, sthaanaani, aashayaaha.
The below mentioned are the different names or synonyms of all the visible and invisible srotases available in the body – Sira, Dhamani, Rasaayana, Rasa vaahini, Naadi, Panthaanaha, Maargaaha, Shareera chidraani, Samvruta-asamvruta, Sthaana, Aashaya, Niketa etc
Types of Strotas
The Srotas are of two types –
Bahir mukha srotas (Mahanti srotas) – External openings or apertures
Antar mukha srotas (Sukshma srotas or Yogavahi srotas) – Internal channels of the body
1. Bahirmukha Strotas – External Orifices
They are 10 in number :
2 each in nose (nostrils), ears (external ear openings) and eyes (orbital openings), 1 each in the penis, mouth (oral cavity) and anal orifice, the 10th one is located in the head
In women there are 3 more orifices – 2 in stana (breasts) and 1 in garbha vartma (cervical opening or opening of the birth canal)
2. Antarmukha Strotas /Yogavahi Strotas – Internal Body Channels
Antarmukha srotases are those channels which are present inside the body. They also have their openings within the body. They are known as Yogavahi Srotas. The word Yoga means a dravya (matter or material a srotas carries) as the srotases carry Rasa and other dhatus.
According to Charaka there are 13 main Antarmukha Srotases. They are –
- Pranavaha Srotas – Channels carrying the vital life element or air
- Udakavaha Srotas – Channels carrying water and controlling water metabolism
- Rasavaha srotas – Channels carrying the nutritional essence
- Raktavaha Srotas – Channels carrying the blood
- Mamsavaha srotas – Channels carrying muscle tissue
- Medovaha Srotas – Channels carrying fat tissue
- Asthivaha Srotas – Channels transporting the bone tissue
- Majjavaha Srotas – Channels carrying the bone marrow tissue
- Shukravaha Srotas – Channels carrying the semen or reproductive tissue
- Mutravaha srotas – Channels carrying urine out of the body
- Purishavaha Srotas – Channels carrying stools out of the body
- Swedavaha Srotas – Channels carrying the sweat
For details on all strotasas, Check the other posts on Ayurvedopedia descibing them.