Gonadotropin and Testosterone Secretion in Normal Human Males After Stimulation With Gonadotropin-Releasing Hormone (Gnrh) or Potent Gnrh Analogs Using Different Modes of Application

Gonadotropin-releasing hormone (GnRH) and some potent long-acting GnRH analogs, applied by different routes of administration, were tested in six healthy human males. The effects on gonadotropin secretion were compared with the one after intravenous (i.v.) bolus injection of 25 microgram of GnRH. The net increase of luteinizing hormone (deltaLH) in serum produced by 25 microgram of GnRH i.v. was matched by subcutaneous (s.c.) injection of 100 microgram of GnRH, dissolved in 20% gelatin or without gelatin; 5 microgram of D-Ser (TBU)6-des-Gly10-GnRH-ethylamide i.v.; 5 microgram of D-Leu6-des-Gly10-GnRH-ethylamide i.v.; and 50 microgram of D-Trp6-des Gly10-GnRH-ethylamide given pernasally (p.n…