Interventional study demonstrates prolonged gonadotrophin and gonadal steroid release after LH-RH analogue administration in healthy men, indicating high biological potency.
Key Points
To evaluate the endocrine effects of the LH-RH analogue D-Ser(TBU)6-EA10-LH-RH on the secretion of gonadotrophins, gonadal steroids, and other pituitary hormones in healthy men.
Healthy male subjects received sequential intravenous injections of 1.0, 2.5, 5.0, and 10.0 µg of the LH-RH analogue at 4-day intervals.
Plasma concentrations of LH, FSH, testosterone, oestradiol, HGH, prolactin, TSH, and cortisol were measured at timed intervals following each dose.
Doses of 1.0 and 2.5 µg stimulated LH release without altering FSH, whereas 5.0 and 10.0 µg produced dose-dependent increases in LH and notable elevations in FSH.
Peak concentrations occurred at 30 minutes for LH and 120 minutes for FSH, with elevations lasting 8 to 10 hours; the 5.0 µg analogue dose achieved LH peak levels comparable to 100 µg of native LH-RH.
Higher doses (5.0 and 10.0 µg) prompted delayed increases in testosterone and oestradiol secretion, while HGH, TSH, prolactin, and cortisol levels remained unaffected.