REGENERATION OF THE TESTICULAR INTERSTITIAL COMPARTMENT AFTER ETHANE DIMETHANE SULFONATE TREATMENT IN THE HYPOPHYSECTOMIZED FROG RANA-ESCULENTA - INDEPENDENCE OF PITUITARY CONTROL

The effects of ethane dimethane sulfonate (EDS) on the testes of hypop hysectomized frogs (Rana esculenta) were investigated by light and ele ctron microscopy. Initial signs of interstitial cell damage were obser ved in EDS- and EDS plus pituitary homogenate (PH)treated animals 5 da ys after a single injection of EDS (100 mg/Kg body weight). The germin al compartment in these two groups appeared disorganized adjacent to t he damaged interstitial tissue only in the EDS-treated animals, and by Day 8, spermatogenesis seemed to be affected in the EDS + PH-treated frogs in which Leydig cells had disappeared in some areas. On Day 28, regeneration of the interstitial tissue was complete and spermatogenes is was restored to normal. These data suggest that, in hypophysectomiz ed frogs, the regeneration of the interstitial compartment is independ ent of pituitary activity and that the lack of interstitial cells acti vates the production of local factors responsible for the differentiat ion and proliferation of new Leydig cells. It is concluded that in add ition to gonadotropins, the intratesticular environment is fundamental in the maintenance and regulation of testicular structure and functio n. (C) 1994 Academic Press, Inc.