Morphological study on the interstitial tissue of the testes

Abstract

The following conclusions were obtained from the histochemical and electron-microscopic findings of the interstitial tissue of the testes in the studies of the experiments using rats and of the clinical materials.1) Interstitial cells (Leydig) are thought to be originated from tunica propria of the seminiferous tubules and the endothelial cells of capillaries.2) The life history of the interstitial cell could be divided in four stages from the electronmicroscopic observations. Smooth-surfaced endoplasmic reticulums, which have close connection with active production of the male sex hormone, are present abundantly in the cells of stage II and III. Such cells are demonstrated by ordinary hematoxylin-eosin stain to be a polygonal cell, cytoplasma of which is large and well stained with eosin.3) Primitive interstitial cell has a bipotentiality of differentiation either to be a secretory cell or to be a connective tissue cell. Cessation of the gonadotrophic function brings about the connective tissue cells. However, administration of the gonadotrophic hormone has no influence upon thus transformed cells to regain secretory function.4) Electron-microscopic studies revealed that administration of androgen caused the interstitial cells to fall into inactive atrophy, while estrogen destructed the interstitial cells.5) Thickening of the walls of the seminiferous tubules is due to increase of the layers of the endothelioid cells in tunica propria. In such a case collagen fibrils appear remarkedly in the interstitial tissue. Both changes, which can be recognized easily by azan stain, reveal the pathologic process of the testes as well as the changes of Leydig's cells.6) In testes of hypergonadotrophic hypogonadism, hyperestrogenism and cryptorchidism, the interstitial cells with lots of pigment granules were observed frequently by the electronmicroscope. Such cells are thought to correspond with the cells which show positive reaction with PAS stain.7) Fibrosis of the interstitial tissue is especially prominent in the testes of the hypergonadotrophic hypogonadism.8) Fibrosis of the interstitial tissue is conspicuous also in the undescended testes. This change remains unrecovered after orchidopexy. The interstitial cells with pigment granules are observed on both operated and non-operated sides of an undescended testis after adolescence.9) In a case of hyperestrogenism interstitial cells consist exclusively of cells with pigment granules or showing marked destruction.10) Fibrosis of the interstitial tissue was found in the testis of a 27 year old patient who had been impotent since trauma of his back.11) Conclusively, three methods of staining, that is, hematoxylin-eosin, azan and PAS stain, are essential for the daily practice of the histological study of the testes.