A 90-day subcutaneous toxicity and fertility study of a LHRH antagonist in rats.

[Ac-D2Nal1,4Cl-DPhe2,D3Pal3,Arg5,DGlu6+ ++ (anisole adduct),DAla10]-GnRH (Nal-Glu) is an antagonist of LHRH and has the potential to be utilized as an antigonadal agent. A study was undertaken to evaluate the toxicological effects of Nal-Glu in rats. Nal-Glu, dissolved in 5% mannitol in water containing 9 ml/liter benzyl alcohol, was administered subcutaneously.

Effect of sulfasalazine and its analogs on fertility in male rats.

Several derivatives of sulfasalazine were tested for their antifertility activity in male rats. The compounds were administered to groups of rats daily by oral gavage for 28 days. Fertility of the rats treated with sulfasalazine or compound CH 74A was reduced, while other compounds had no effect.

Reversal of testicular function after prolonged suppression with an LHRH agonist in rhesus monkeys.

Using subcutaneously implanted osmotic pumps, four male rhesus monkeys were continuously infused for 18 months with 100 micrograms/day of [(imBzl)-D-His6-Pro9-NEt]-LHRH (LHRH-A), a potent agonist of LHRH. After an initial increase, serum testosterone levels declined to 10% of pretreatment levels in three monkeys and the response to electroejaculation was lost. There was a decrease in testicular volume.