INHIBITION OF SPERMATOGENESIS IN THE RAT BY TREATMENT WITH (D-Ala

The effect of treatment with a potent LHRH agonist, (D-Ala , Des-Gly- N^-^lLHRH ethylamide, injected at the low dose of 100 ng, twice a week, was evaluated on spermatogenesis in the rat. Significant degenerative changes of seminiferous tubules could be observed after two weeks of treatment. These changes were progressive and led to a marked inhibition of spermatogenesis after four to eight weeks of treatment. Testis weight was decreased to appro- ximately 50% of control after eight weeks of treatment.