The Occurrence of Oviform Germ Cells by Hormonal Injection in the Regenerated Testes of a Newt

抄録

a) Triturus pyrrhogaster has multiple testis made up of two or more small successive lobes. In each testicular lobe certain wave of germ cell differentiation proceeds in cephalo-caudal direction. The spermatogenesis begins at the cephalic end of the lobe and the more the tubules shift caudally they contain the germ cells of the more advanced stages and its caudal end is occupied by the senescent tissue which had extruded the reproductive products in the preceding breeding cycle. At the cephalic apex of the lobe there remains permanent embryonal tissue which supplies the germ cells in the succeeding breeding season. The last named region is readily distinguishable as a white crest at the apex of the lobe.
b) When the male is incompletely castrated the tissue of white crest regenerates very well. Spermatogenesis performed in the regene-rated testis agrees in general with that in the normal male.
c) The white crest of the testicular lobe regenerates equally well, whether grafted in completely castrated male or female. Grafts from the central region of the testis containing only matured spermatozoa degenerate and eventually disappear.
d) In a small number of regenerated testes oviform germ cells of various sizes differentiated intermingling with matured spermatozoa.
e) When incompletely castrated male was injected with pelanin benzoate, a preparation of crystalline follicular hormone dissolved in sesame oil, differentiation of oviform germ cells occurred in the majority of cases to a considerably high degree. The injection was executed every month over the range of about one year. Some oviform cells appeared singly in the intervening tissue of seminiferous tubules, others within the confines of tubules, but those developed in the broad connective tissue zone of rather abnormally regenerated testes were largest in size as well as in number. In an extreme case about two-thirds of the entire volume of the regenerated testis was packed with oviform cells of various sizes. The seminiferous tubules neighbouring the connective tissue containing oviform cells are more or less retarded in their spermatogenetic activity.