Increased luteinizing hormone sensitivity to dopamine inhibition in polycystic ovary syndrome.

The elevated LH secretion in 8 patients with the polycystic ovarian syndrome (PCO) was promptly suppressed by the infusion of dopamine (DA; 4 microgram/kg.min for 4 h). Compared to normal women studied during the early follicular phase, the maximal LH suppression due to DA infusion was significantly greater in PCO patients when expressed as either the net or percent decrease. This enhanced LH sensitivity to DA inhibition in PCO patients with chronically elevated estrogens, suggests that the inappropriately elevated LH release and the exaggerated LH pulses may be causally related, in part, to a reduction of endogenous DA inhibition of LH secretory activity.