Temperature Dependence of Sertoli Cell Function

Spermatogenesis as well as Sertoli cell function, monitored by ABP secretion, is severely impaired at 37°C in vivo and in vitro. A closer understanding of the biochemical mechanisms behind this phenomenon may lead to future methods for fertility control. The cryptorchid Sertoli cell was shown to be exposed to normal or increased levels of the two main stimulatory hormones, testosterone and FSH. Androgen receptor concentrations in hypophysectomized rat testes were not changed by cryptorchidism. However, FSH and to some extent LH receptors showed a gradual decline during 28 days of cryptorchidism. Even in the absence of hormones, Sertoli cells in vitro produced less ABP at 37 than at 32°C. This shows that 1) Testicular FSH receptors can be practically eliminated in vivo. 2) The basal secretion of protein by the Sertoli cell, in the absence of hormones, is impaired at elevated temperature. An elucidation of the biochemistry involved in that impairment may also yield possible points of attack in the search for a male contraceptive.