Modulation of basal and LRH-stimulated gonadotrophin secretion by histamine in normal men.

The effects of histamine (HA) and of HA in combination with H1- and H2-receptor antagonists on basal and LRH-receptor antagonists on basal and LRH-stimulated LH and FSH secretion were investigated in 10 normal men. HA enhanced the LH response to LRH (p less than 0.05), but had no effect on basal LH secretion. The enhancement of LRH-stimulated LH secretion was not observed when either an H1- (mepyramine) or an H2- (cimetidine) receptor antagonist was administered concomitantly with HA. Cimetidine administered alone had no effect on basal or LRH-stimulated LH secretion. HA had no effect on basal or LRH-stimulated FSH secretion. We conclude that the effect of HA on LRH-stimulated LH secretion is mediated through a combined stimulation of H1- and H2-receptors.