Somatostatin-28 inhibits LHRH-stimulated gonadotrophin secretion in man.
The LH and FSH responses to 100 micrograms LHRH in a combined pituitary stimulation test were compared to five normal men during infusions of somatostatin-28 (SS-28) and somatostatin (SS-14) and during control infusions of haemacel. SS-28 and SS-14 were administered in equimolar concentrations of 1.8 nmol/kg body weight over 210 min and LHRH was injected as a bolus at 120 min after commencement of the infusion. SS-28 significantly reduced both LH and FSH responses to LHRH compared with control infusions. SS-14 did not significantly alter the FSH response but caused a significant reduction in the LH concentration 75 and 90 min after LHRH injection. These findings demonstrate that SS-28 has distinct biological activity in addition to its role as a putative precursor of SS-14. Inhibition of gonadotropin hormone secretion by SS-14 and SS-28 suggest that these hypothalamic peptides may play a part in the regulation of LH and FSH secretion.
D000328:Adult; D003864:Depression, Chemical; D005640:Follicle Stimulating Hormone / Q000378:metabolism*; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D007986:Luteinizing Hormone / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors / Q000494:pharmacology*; D013004:Somatostatin / Q000494:pharmacology*; D053561:Somatostatin-28
D011498:Protein Precursors; D007987:Gonadotropin-Releasing Hormone; D013004:Somatostatin; D053561:Somatostatin-28; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone