Comparison of the Species Specificity of Gonadotropin Binding to Primate and Nonprimate Corpora Lutea

Publisher Website
Google Scholar
Abstract
The effects of human chorionic gonadotropin (hCG) and estradiol-17β (E2) on testicular blood flow and plasma testosterone concentrations were measured in rats. Injection of 100 IU hCG 20-24 h prior to experiment resulted in a significant rise in testicular blood flow and plasma testosterone concentration. Daily treatment with 50 µg E2 for 5 days did not affect testicular blood flow but induced a significant depression of plasma testosterone concentration. However, E2 treatment did partly diminish the stimulatory effect of hCG on both testicular blood flow and the concentration of testosterone in plasma. It was concluded that blood flow changes are involved in the effect of hCG on testicular endocrine function and that E2 can partly inhibit these effects.