AUTORADIOGRAPHIC STUDY OF LYSINE AND ARGININE INCORPORATION STIMULATED BY FOLLICLE-STIMULATING HORMONE IN THE MOUSE TESTIS IN VIVO

Abstract

Hypophysectomized adult mice were given injections of highly purified FSH 12 h before killing, and of tritiated lysine or arginine 2 h before killing. Autoradiographs were prepared from paraffin wax sections of testes. Treatment with FSH increased the density of silver grains over the nuclei of the Sertoli cells and of all types of germinal cell except the early spermatids. The stimulatory effect of FSH on incorporation of both lysine and arginine was most marked in the nuclei of preleptotene primary spermatocytes. The ratio of arginine to lysine incorporation was greater in spermatids undergoing nuclear elongation than in other types of cell.