脊椎動物睾丸の間細胞に就て

Abstract

(1) The origin and fate of interstitial cells in the testis of the following animals were confirmed by histological study:Adult vertebrates:Middle Yorkshire swine. Frog (Rana nigromaculata HALLOWELL). Toad (Bufo vnlgaris japonicus SCHLEGEL). Water-lizard (Diemyctylus pyrrhogaster BOIE). Roach (Akahara Hahoneusis GÜNTHER).Young frogs. Pigs. Pig embryos.For the purpose of comparison with vertebrates, the testis of locusts (Oxya japonica WILLENSE, O.velox Fabricus) and silk worms (Bombyx mori Linnaeus) were also sectioned.(2) In silk worms, there exist no cells corrsponding morphologically to Leydig's cells as in mammals.(3) In water-lizards there are isolated interstitial cells found, as well as these groups, surrounded by thin fibrinous membane.(4) The development of interstitial cells delay in some degree, as compared with the increase of germinal elements.(5) It is proved that interstitial cells are of the manifold origin, in general stroma as well as Sertoli and follicle cells being the main sources of their formation.a) The majority of interstitial cells arise from stroma cells in most animals, except those of the testes of ducks of which the considerable number of them spring from Sertoli cells.b) In all animals, so far as investigated, Sertoli and follicle cells may be converted into interstitial cells. This process is correlated with the degeneration and resorption of germ cells, probably due to the physiological action of the readjust ment of spermatogenesis. in accordance with the development of testis.c) It would seem also proboble that interstitial cells are derived from cells of the Tunica propria of the spermatic tubules at least in urodeles, roaches and locusts and presumably those of anurans, in addition epithelial elements of the sperm collecting ducts in frogs and toads.(6) There exist two stages of proliferation of interstitial cells in pigs in an embryonic life, of which the first one is of 37 days old and the second is 100 days old.(7) Great variability occurs in number and size of interstitial cells during yearly spermatogenetic cycle. In ducks, it is reduced to a minimum near the height of spermatogenetic activity, that is, shortly before gradual return to completely inactive conditions of the non-breeding season, when testis begin to decrease in size and interstitia cells get more difficult to recognize as such and they are almost lacking in some testis.Although, in other adult animals, the number of them, having the cytoplasm filled with a great number of mitochondria and droplets of fat as well as well-developed Golgi apparatus are greatest and the testis are supplied abundantly with blood vessels during the breeding season and at the time when young animals reach the full sexual maturity.(8) The appearance of the secondary sexual characters precede the great increase in number of interstitial cells, at the time when the testis is in complete spermatogenetic activity, with the presence of mature spermatozoa in almost every sperrnatogenic tubules.(9) The stage of the maximam number and secretory activity of interstitial cells is simultaneous with the stage of the intense appearance of the typical feature of the secondary sexual characters and later on, there seems to be parallel relationship between them.(10) In adult animals, there are ldcal variations in the spermatogenic activity in the same testicle. Interstitial-cell changes bear the reverse relation to conditions of germinal elements; that is to say, interstitial cells develop only when spermagenic tubules are inactive and intertubular spaces wide, and then gradually regress when tubules are in active spermatogenesis and intertubular spaces narrow.