Kalas Embryological Aspect with Reference to its Origin

Abstract

Kala sharir is an important part of ayurvedic anatomy. It is a unique subject as well as difficult to understand. Acharya Sushrut was the first to explain Kala in 4th chapter of Shareer sthan named “Garbha Vyakran Shareer”. Acahrya Sushruta has defined the Kala as limiting or separating Membranes between Dhatu and Ashaya. These are extremely minute particles and in visible to naked eye, similar to cell. They can be understood by their functions in the body. There are seven Kalas in our body - Mamsdhara, Raktadhara, Medodhara, Shleshmadhara, Pureeshdhara, Pittadhara, Shukradhara kala. [1] Kala can be correlated with Membrane, Fascia, Covering etc. structures as per contemporary science. Membrane may be fibrous, serous and mucous. Membrane are formed during the embryonic period. Here an attempt is made to understand the formation of kala on the basis of Ayurvedic and modern view.

Introduction

I. INTRODUCTION

Rachana Sharir (Anatomy) is the branch of Ayurveda which deals with the structure of the body. Kala Sharir is a distinct idea of Ayurvedic Rachana Sharir. Kala are regarded as restricting membranes that exist between Dhatu and Aashay. In the body, Kala perform many functions besides as restricting membranes between two substances like Formation, Protection, Absorption & Secretion. The term "Kala" denotes a Guna or attribute and describes its physiological component.

Acharya Sushruta defines Kala as sheath-like structures encased in Shleshma or mucoid substance. They have also been identified as the inner most limiting linings of Dhatu (tissue) and Ashaya (body cavities). Kala are known as membranes or layers in current anatomical terminology. Membrane called as a paliable sheet like structure acting as a boundary, lining or partition in an organism. They provide support & protection to the organs. There are many membranes in the body, however Ayurved compendia only mentioned seven Kalas in the body, therefore the precise idea of Kala has to be investigated on this basis. Similarly, while Sushruta and other acharyas provided detailed description about Kala, its embryological aspect is not extensively developed. Kala, like other organs, are significant structures in the body, hence an all-dimensional study is necessary.

A. Aim & Objectives

Exploration of embryological aspect of Kala Sharir according to Ayurved and modern perspective.

II. MATERIALS & METHODS

Ayurved compendia, modern textbooks, research papers and articles related to topic were extensively studied.

A. Literary Review

Ayurvedic perspective

Acharya Sushrut was the first who described Kala. He defined Kala as “Dhatvashyaantar maryada” [2] means Kala are intervening/limiting structure between Dhatus (Rasa, Rakta) and their seat Ashayas (viscera). He illuminated as when we cut the wood we can see its pith, duramen or core; similarly, we can see the internal Dhatus of our body by removing the successive layers or tissues of its flesh. [3]

The formation of Kala has been explained by Acharya Vagbhat in Astanga Sangraha first time. According to Ashtanga-sangraha, the moisture (Kleda) that stays inside the Dhatus (tissues) and Ashaya (organs), is cooked (processed) by the heat existing in them (tissues) and creates structures similar to those found in wood (tree) which is called as Kala. [4] Because it is made up mostly of the essence of Dhatus and a very small amount of Rasa, it is known as Kala. Other acharyas also have given the almost same explanation regarding the formation of Kala which is similar to that of Astanga Sangraha.

A few Ayurvedic literature viewpoints on Utpatti of Kala are as follows:

1. Ashtanga Sangraha: Very little quantity of Rasa & essence of Dhatus
2. Ashtanga Hridaya: Kleda between Dhatu & Ashaya [5]
3. Sharangdhar: Moisture present in Dhatus [6]
4. Bhavaprakash: Kleda inside Dhatu, Ashaya and Dhatvantara - cooked by heat of body tissues [7]

These Kalas are extensively covered with Snayus (fibrous tissues), spread as membranous structure like amniotic membrane (Jarayu) and smeared with Shleshma (mucous). [8] All these three structures may or may not necessarily be present in each Kala, even one or two of the above?mentioned structures may be found existing in the Kala.

• Snayu signifies ? structural support
• Jarayu signifies ? barrier/selective permeability
• Shleshma signifies ? lubrication and nutrition [9]

B. Modern Perspective

To understand Kala in relation to modern anatomy, it would be appropriate to start with the understanding of tissue.

Body Tissue: The human body is made up of many types of tissue. A tissue is a group of cells having similar structure and function. These cells work together as a single unit. Primary types of tissue are as follows:

1. Epithelial Tissue: Cells are organised in the epithelium into continuous sheets. They cover body cavities, hollow organs and entire surface of the body. They are major components of the glands.
2. Connective Tissue: Adipose tissue, loose connective tissue, and thick connective tissue are all types of connective tissue. Special connective tissues include blood, cartilage, and bone.
3. Muscular Tissue: This is of three types viz. Skeletal, cardiac and smooth muscles.
4. Nervous Tissue: This tissue consists of neurons, nerve cell processes and cells of neuroglia. [10]

C. Epithelium

The layer that covers the body surfaces is termed as epithelium. Epithelia described in contemporary science have similarity with Kala described in Ayurved. Embryologically, epithelia are developed from all three germ layers, i.e., ectoderm, endoderm, and mesoderm. Here are a few instances of these:

1. Epithelia from Ectoderm: Epithelium of skin, hair follicles, sweat glands, sebaceous glands and mammary glands. Epithelium over cornea and conjunctiva, external acoustic meatus and outer surface of tympanic membrane. Epithelium of Some parts of the mouth, lower part of anal canal, terminal part of male urethra, parts of female external genitalia.
2. Epithelia from Mesoderm: Tubules of kidneys, ureter, trigone of urinary bladder, uterine tubes, uterus, part of vagina, testis and its duct system, endothelium lining the heart, blood vessels and lymphatics, mesothelium lining the pericardial, peritoneal and pleural cavities and cavities of joints
3. Epithelia from Endoderm: Epithelium of entire gut except part of the mouth and anal canal (lined by ectoderm), auditory tube and middle ear, respiratory tract, epithelium over part of urinary bladder, urethra and vagina.

Epithelium with its underneath connective tissue can be detached as a single layer, which is known as a membrane. If the surface of a membrane is moistened by mucous glands, it is called a mucous membrane or mucosa and when a similar layer is covered by mesothelium is called a serous membrane or serosa.

The mucous membrane lines interior of hollow organs and the body cavities that open outside viz GIT, respiratory, urinary and reproductive systems. Mucus membranes are involved mainly in the functions of various types of secretion and absorption.

Serous membranes: The body cavities that do not open outside are lined by this membrane. Also, the organs lying within such cavities are covered by this. Pleura, pericardium and peritoneum are the examples of serous membranes.

III. DISCUSSION

In general, the term "Kala" denotes a little piece, particularly a sixteenth part, of anything, as well as any single part or portion of a total. (Rigveda 7,47,17). This shows that Kala are minute structures in the body that play a role according on their location.

All the Kala are classified as Snayu-pratichhanna, Jarayu-santat and Shleshma-veshtit, which correspond to the contemporary names fibrous, serous and mucous membranes, respectively. In case of Snayu-pratichhanna the word tendinous sheath is used in certain books. Tendons are fibrous parts of muscles found throughout the body. The Kala specified in Ayurved is found precisely at the locations mentioned in its categorization. The fibrous membrane is a particular kind of membrane that covers various bodily tissues in several places. The deep fascia is a layer of thick, fibrous connective tissue that separates groups of muscles into fascial compartments and covers individual muscles. This fascia is quite similar to the Mamsadhara Kala mentioned in Ayurved. As a result, the phrase Snayu-pratichhanna used in reference to Kala should be interpreted as fibrous membrane.

Similarly in case of Jarayu-santat, some writers claim that Jarayu is the chorionic membrane, it is actually a component of embryonic life that is descended from the chorion. Chorion takes part in the formation of placenta. Amnion is another tissue which is generated from extraembryonic mesoderm and amniogenic cells. It creates the amniotic membrane that can be associated with Jarayu. As Jarayu is said to be one of the form of Kala, it is present in post embryonic life also. Serous membrane is a similar type of membrane that is found in the body and secretes a little amount of fluid to reduce friction. Serous membranes are the internal coverings mostly associated with body cavities. As a result, the name Jarayu in Ayurved should be associated with the serous membrane rather than the chorionic membrane.

Another kind of Kala that is described by practically all Aacharyas is shlemana-veshtita. Although Shleshma is associated to Kapha, it is a subtype of Kapha that is responsible for lubrication. The Shleshmadhara Kala, which is referenced in Ayurved and is located in moveable joints, has a primary role of lubricating. The mucous membrane described by modern science is similar to the Shlemana-veshtita kind of Kala described by Ayurved because the functions are mostly similar.

Sushruta's description of the Aantra Utpatti can serve as a reference for comprehending Kala's Utpatti. Aantra are generated when Vayu penetrates the essence of Rakta and Shleshma during their Pachan by Pitta. In case of intestine mucous membrane is present between hallow and muscular part. According to the preceding explanation of Aantra Utpatti, the essence of Rakta may contribute to the production of muscle tissue, while the essence of Kapha may contribute to the formation of mucous membrane. Both Rakta and Kapha have a major liquid quality, that is compatible with the liquid element for the production of Kala. Thus, the essence of Kapha or its component, as well as some essence from tissue, may play a role in the development of Kala.

In contemporary terms, the development of Kala can be explained by the production of tissue. In the Material & Method section, information about bodily tissues and their derivatives from diverse epithelia is gathered. The Kala mentioned in Ayurvedic literature is similar to the epithelia described in embryology. Previous writers have already compared Sapta Kala to contemporary anatomical structures. The following table provides an overview of these structures by comparing them to their embryological development.

Table: SaptaKala and Modern Anatomy Correlation

Conclusion

The seven Ayurvedic Kalas should be compared to the bodily membranes. The creation of Kala is caused by a liquid component that is present between body tissue and the hollow space. The liquid component may be Kleda, moisture or essence of Dhatus. The main factor in the development of Kala is Kapha or the essence of Kapha and based on the influence of Vata and Pitta, it is classified as Snayu-pratichhanna, Jarayu-santat, and Shleshma-veshtit. Ayurvedic Kala can be classified as epithelium, mesothelium or endothelium coverings of predominantly mesodermal and endodermal origin.

References

[1] Ambika Dutt Shashtri, Ayurved Tatva Sandipika Hindi Tika, Sushrut Samhita, Chaukhamba Prakashan, Varanasi, 2014, Vol. 1, Sharir Sthan 4, Shloka 5, page no.38. [2] Ambika Dutt Shashtri, Ayurved Tatva Sandipika Hindi Tika, Sushrut Samhita, Chaukhamba Prakashan, Varanasi, 2014, Vol. 1, Sharir Sthan 4, Shloka 5, page no.38. [3] Ambika Dutt Shashtri, Ayurved Tatva Sandipika Hindi Tika, Sushrut Samhita, Chaukhamba Prakashan, Varanasi, 2014, Vol. 1, Sharir Sthan 4, Shloka 6, page no.38. [4] Vaidya Pandit Ramchandra Shastri Kinjwadekar, Ashtanga Sangraha, English Inroducion by Vaidya Bhagwan Dash, Sri Satguru Publications, reprint edition, 1990, page no. 115. [5] Dr. Brahmanand Tripathi, Nirmala Hindi Tika, Astanga Hrdaya, Chaukhamba Sanskrit Pratishthan, Delhi, 2015, Sharir Sthan 3, Shloka 9, page no. 368. [6] Sharangadhar Samhita, Edited by K.R. Murthy, Chaukhamba Orientalia, Varanasi, 2016, Purva Khanda, Chapter 5, page no. 20-21. [7] Bhavamishra, Bhavprakash, Edited by Murthy KRS, Chaukhamba Krishnadas Academy, Varanasi, 2016, Vol-I Purvakhanda, Chapter 3-Garbhaprakaranam, page no. 48 [8] Dr. Bhaskar Govind Ghanekar, Sushruta Samhita: Sharirsthanam, Ayurved rahasya deepika hindi tika, Meherchand Lacchamandas Publications, New Delhi, reprint edition Jan. 2018, Chapter 4, Shlok no. 6, Page no. 108. [9] Soni G., Analytical study of Kala Sharir on the principles of histology, Journal of Ayurveda, Volume 15, Issue 1, January-March 2021, page no. 55-60. [10] Inderbir Singh, Human Embryology, Jaypee Brothers Medical Publishers, New Delhi, 10th ed., 2015, Chapter 7 - Formation of Tissues of the Body, page no. 95 [11] Dr. Sachin Khedikar, “Kalaanveshan-2019?

Copyright

Copyright © 2023 Dr. Saurabh Chandra Rohila, Dr. Hemendra Kr. Verma, Dr. Shyoram Sharma. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.