R Soldani

Evidence that an altered prolactin release is consequent to abnormal ovarian activity in polycystic ovary syndrome

OBJECTIVEnTo investigate whether endogenous dopaminergic activity is impaired in polycystic ovary syndrome (PCOS)-affected women and is normalized by medical ovariectomy.nnnPATIENTSnWomen with PCOS untreated (n = 23) and treated for 3 months with GnRH analogue (GnRH-a) administration (n = 10) and normal cycling young women (n = 23) as controls.nnnINTERVENTIONSnAcute blockade of dopaminergic receptors by the IV administration of 5 mg of the dopaminergic receptor blocking agent sulpiride (sulpiride test) was performed 3 to 7 days after the initiation of spontaneous menses in cycling women or medroxyprogesterone acetate-induced menses in PCOS women. In PCOS women treated with GnRH-a administration (goserelin depot, 3.6 mg SC every 28 days), the sulpiride test was repeated 10 to 15 days after the third GnRH-a administration.nnnMAIN OUTCOME MEASUREnBasal PRL levels and PRL increase induced by sulpiride.nnnRESULTSnBasal PRL levels and the PRL response to sulpiride were increased in women with PCOS. In women with PCOS medical ovariectomy induced by GnRH-a administration reversed to normal both basal and sulpiride-stimulated PRL levels.nnnCONCLUSIONSnIn women with PCOS the abnormal regulation of PRL and presumably of hypothalamic neurotransmitters controlling PRL secretion is not a primary alteration but it is likely dependent on abnormal ovarian functionality.

Prolonged opioid blockade with naltrexone and luteinizing hormone modifications in women with polycystic ovarian syndrome.

OBJECTIVEnTo investigate whether enhanced LH levels of women with polycystic ovarian syndrome (PCOS) are the consequence of an absent hypothalamic opioid inhibitory control and/or an increased sensitivity of gonadotroph to GnRH, induced by sensitizing effects of circulating opioid peptides.nnnDESIGNnPulsatile LH secretion (10-minute sampling for 6 hours) and GnRH-stimulated (10 micrograms) LH release were investigated in 14 women with PCOS before and after the 5-day administration of placebo (n = 7) or the opioid antagonist naltrexone (50 mg/d; n = 7). Seven age- and weight-matched normal cycling women in follicular phase were used as controls.nnnRESULTSnIn comparison with normal cycling women, PCOS showed normal frequency and increased amplitude LH pulses, elevated mean LH levels, and increased LH response to GnRH. In PCOS, placebo administration was not associated with any LH modification, whereas naltrexone enhanced the frequency and decreased the amplitude of LH pulses, without modifying mean LH levels and the LH response to GnRH.nnnCONCLUSIONSnThe naltrexone-induced increment of LH frequency revealed a conserved central opioid tone in PCOS. Reduced LH pulse amplitude, induced by naltrexone, was not associated with a reduced LH response to GnRH or with a reduction in mean LH levels. Present data do not support a role for endogenous opioid peptides in the pathogenesis of increased LH levels in PCOS.