[Trigger properties of gonadotropic hormones and oocyte factors in connection with the germinal epithelium of the rat testis].
In order to reveal possible stimulation of growth of the germinal epithelium of the rat's injured testicle the animals were injected follicle-stimulating and luteinizing hormones and their mixture as well as homogenate of fertilized egg-cells during two weeks. Changes of neurosecretion in large-cell nuclei of the anterior hypothalamus, cellular set in the adenohypophysis and the condition of the germinal epithelium in the gonad under study were investigated. Identical phenomena of reduction (having quantitative distinctions) took place due to effects of exogeneous honadotropins in neurosecretory nuclei and the adenohypophysis. In testicular tubules there occurred pronounced proliferation of the germinal epithelium, but spermatogenesis was absent. Egg-cell homogenate failed to cause changes in neurosecretion and adenohypophysis but resulted in completing the developmental cycle of the germinal epithelium with mature spermatozoa. The effect of gonadotropins upon the system hypothalamus-hypophysis is explained by feed-back mechanism, and the absence of spermatogenesis--by the lack of androgens. The rsults of egg-cell homogenate effects should be associated with local stimulating effects of DNA of the dividing egg-cell.