Open AccessEXISTENCE OF A SPERMATOGONIAL CHALONE IN THE RAT TESTIS
Author(s) -
Clermont Yves,
Mauger Annick
Publication year - 1974
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1974.tb00408.x
Subject(s) - saline , endocrinology , biology , physiological saline , medicine , irradiation , testicle , population , andrology , significant difference , physics , environmental health , nuclear physics
Adult rats with normal or X‐irradiated testes were used in an experiment to test the possible existence of a chalone in the testis. On the 11th day following irradiation, i.e. as the type A spermatogonia proliferated actively to restore the partially destroyed spermatogonial population, the animals with irradiated testes were subdivided into three groups. Rats of the first group were injected intraperitoneally with a saline extract of normal adult rat testes. Animals of the second group were injected with an equal amount of physiological saline while the rats of the third group received equivalent injections of a saline liver extract. Two additional groups of rats with non‐irradiated testes, injected with the testicular extract or saline solution, served as controls. Following the last injection all animals were injected with 3 H‐thymidine and sacrificed. From each animal one testis was used to determine the specific radioactivity of its DNA, the other testis was processed for radioautography. The testicular extract produced a significant decrease in uptake of radioactivity by the irradiated testes. There was no difference in the radioactivity uptake by the testes of non‐irradiated rats. Correspondingly the labeling index of type A spermatogonia was significantly lower in animals of the first group than in the other two groups of animals with irradiated testes. However, there was no difference in the labeling indices of Intermediate and type B spermatogonia or of preleptotene spermatocytes in the animals receiving the extracts or the saline solution. In animals with non‐irradiated testes there was no difference in the labeling indices of type A or other types of spermatogonia or of spermatocytes. These data were taken to indicate that a saline extract of normal adult testes contains a substance that can inhibit specifically the proliferation of type A spermatogonia during the repair phase of the spermatogonial population following irradiation. This substance was tentatively considered as a spermatogonial chalone.