What is a Leydig cell

  Thumbnail overview testicles (Testis):
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in the Testicles (Terminologia histologica: Testis, Orchis; English testis) found in large, often winding, many centimeter long corridors (Terminologia histologica:Seminiferous tubules; English seminiferous tubules, convoluted seminiferous tubules) dieSpermiogenesis = Formation and maturation of male germ cells take place. Reaching vertically from the base of the germinal epithelium to the lumen of the ducts are the supporting cells of the testicle = Sertoli cells (Terminologia histologica: Sustentocyti, Epitheliocyti sustentantes; English nurse cells, sustentocytes, supporting cells = Sertoli cells) between the germ cells maturing in different stages. They are connected to one another via tight junctions via lateral runners, which means that the Blood testicular barrier (Terminologia histologica: Claustrum haematotesticulare; English blood testis barrier) emerges. The Sertoli cells of the testicle form an androgen-binding protein (ABP) which binds dihydrotestosterone formed by nearby Leydig cells and excretes this into the seminal fluid so that it can work in the epididymis (see here). While the stem cells thatSpermatogonia A. (Terminologia histologica: Spermatogonia A; English type A spermatogonia) are still below the barrier, the maturing daughter cells get thereSpermatogonia B. (Terminologia histologica: Spermatogonia B; English type B spermatogonia) further up, the tight junctions open and squeeze between the Sertoli cell processes. Above the bar they become tooFirst order spermatocytes (Terminologia histologica: Spermatocyti primarii; English primary spermatocytes), which then under themeiosis, the reduction division to halve the chromosome set after the first meiosis2nd order spermatocytes (Terminologia histologica: Spermatocyti secundarii; English secondary spermatocytes). A special feature are the synaptonemal complexes that occur in the nuclear plasma of first-order spermatocytes when the number of chromatids per chromosome pair doubles from 2 to 4. After only a few minutes, the spermatocytes 2 finish the second meiosis, making them too earlySpermatids (Terminologia histologica: Spermatida; English spermatids). Lace these upResidual body (Terminologia histologica: Corpora residualia; English residual bodies) and thus reduce their cell volume. As part of the Acrosomatogenesis (Terminologia histologica: Acrosomatogenesis; English acrosome formation) is formed from a large lysosome that Acrosome (Terminologia histologica: Acrosoma, Galea acrosomatica; English acrosome, acrosomal cap), which is later necessary for the penetration of the mature sperm into the egg cell. In addition, apart from the centrioles, one of which develops into a long flagellum and the mitochondria practically all other cell organelles perish. Via the intermediate step of the late spermatids, theSperm (Terminologia histologica: Spermatozoa, Spermia, Gameti masculini; English sperms, sperm cells, male gametes; detailed information about sperm here). The still immobile sperm are transported via a flow of fluid caused by the seminiferous tubules into the ducts of the testicular network (rete testis) in the efferent ducts of the epididymis.
Thetestosterone producing Leydig cells (Terminologia histologica: Endocrinocyti interstitiales; English interstitial endocrine cells) lie outside between the tubules and are therefore also called Intermediate cells designated. They often show fat droplets, rarely crystals (Reinke crystals; Terminologia histologica: Crystalloidea; English crystalloid), always a lot of smooth endoplasmic reticulum and numerous mitochondria of the tubular type.

-> Epididymis, seminal vesicle, prostate, epithelium, crystals, blood-testicular barrier, synaptonemal complexes
-> Electron microscopic atlas general overview
-> Homepage of the workshop

Four images were kindly provided by Prof. H. Wartenberg; other images, page & copyright H. Jastrow.