Response of luteinizing hormone and follicle-stimulating hormone to different doses of D-leucine-6-LH-RH ethylamide in oligospermic patients.

The rise in luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels after intramuscular administration of D-leucine-6-LH-RH ethylamide was studied in seven patients with idiopathic normogonadotropic oligospermia. Four tests with 2.5, 5.0, 10.0, and 20.0 mug of the analog, respectively, were carried out at 8 A.M. on each subject. The interval between tests was 1 week. Serum levels of LH and FSH were determined by radioimmunoassay before (-15 And 0 minutes) and 2, 4, 6, 12, and 14 hours after each injection. No differences in the basal values for either hormone were observed. D-Leucine-6-LH-RH ethylamide produced significant increases in LH and FSH levels for 6 to 12 hours after the injection. Peak values were obtained between 4 and 6 hours. A dose-response relationship for both gonadotropins was observed. The highest average levels of LH and FSH were obtained after injection of 20.0 mug of the drug. A great individual variation in magnitude of response was observed which seemed to be related to the functional reserve of the pituitary. It is suggested that doses of 10.0 to 20.0 mug of D-leucine-6-LH-RH ethlamide/day could be used for chronic treatment in male infertility.