Impact
Franz von Leydig's work on neural tissue influenced Norwegian zoologist and polar explorer Fridtjof Nansen (1861–1931), who along with Wilhelm His, Sr. (1831–1904) and Auguste-Henri Forel (1848–1931), were the first to establish the anatomical entity of the nerve cell. Chief among Leydig's discoveries is the interstitial cell ("Leydig cells"), a body enclosed in a smooth endoplasmic reticulum and holding lipid granules and crystals, which occur adjacent to the seminiferous tubules of the testes. The cells are believed to produce the male hormone testosterone. Leydig had described the interstitial cells in his detailed account of the male sex organs.
| “ | The comparative studies of the testis resulted in the discovery of cells surrounding the seminiferous tubules, vessels, and nerves. These special cells are present in small numbers where they follow the course of the blood vessels, but increase in mass considerably when surrounding seminiferous tubules. These cells are lipoid in character; they can be colourless or can be stained yellowish, and they have light vesicular nuclei." -Franz Leydig, 1850 | ” |
The above description clearly indicates that Leydig recognized the specific morphology of those cells: only recently, have their endocrine nature and ultrastructure been fully understood.
In addition to its historical importance, Leydig’s "Lehrbuch" is significant for his description of a large secretory cell, found in the epidermis of fishes and larvae amphibians. This mucous cell is unusual in that it does not pour secretion over the surface of the epithelium; Leydig believed that the cell function was to lubricate the skin, and the cell now bears his name. Leydig is also known for describing large vesicular cells that occur in the connective tissue and the walls of blood vessels in crustaceans in 1883: four different types of the latter have been determined.
Read more about this topic: Franz Leydig
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