LH stimulates the interstitial cells to make testosterone. Clinical problems and solutions GnRH has been linked to causes of several clinical syndromes. Human hypogonadotropic hypogonadism, or Kallmann's syndrome, is the condition where gonadal development is stunted due to a shortage of GnRH to signal the release of the gonadotropins. The syndrome occurs in 1 in 10,000 males and about 1 in 50,000 females. Important characteristics are hypogonadotropic hypogonadism with anosmia, the latter being due to the failure of the olfactory system to fully develop.
Cryptorchidism is the failure of the testicles to descend into the scrotum.
This results in the testicles being kept at 37 C, which is too warm for spermatogenesis. Results to date indicate that suppression of GnRH decreases testosterone to castration levels in dogs, but not in cats. Furthermore, after two years the anterior pituitary was still unresponsive to supplemented GnRH, suggesting permanent impairment. Therefore, more research is needed because permanent sterilization is not always desirable. More than one form has been isolated from the same animal.