Paradisi R, Venturoli S, Capelli M, Spada M, Giambiasi M E, Magrini O, Porcu E, Fabbri R, Flamigni C
Institute of Reproductive Physiology and Pathology, University of Bologna, Italy.
J Clin Endocrinol Metab. 1987 Nov;65(5):841-6. doi: 10.1210/jcem-65-5-841.
Central noradrenergic mechanisms may participate in the regulation of pulsatile gonadotropin secretion in women with the polycystic ovary syndrome (PCO). To examine this possibility we measured serum LH, FSH, and PRL concentrations at 10-min intervals and total testosterone and 17 beta-estradiol at 60-min intervals for 8 h basally and during the infusion of the alpha 1-adrenoceptor antagonist thymoxamine (10 micrograms/kg X min) in 10 young women with PCO. Mean and integrated serum LH concentrations as well as LH pulse frequency were not significantly altered (P = NS) during the thymoxamine infusion. However, we found an increase in LH pulse amplitude as both net (P less than 0.002) and percent (P less than 0.002) increment, as well as mean LH peak values (P less than 0.05) during alpha 1-adrenergic blockade. There were no significant changes in pulsatile FSH and PRL secretion or gonadal sex steroids during these experimental conditions. These data suggest that in PCO patients, 1) brain noradrenergic mechanisms do not play a stimulatory role in regulating the frequency of pulsatile LH secretion, 2) central noradrenergic activity inhibits LH pulse amplitude, and 3) PRL and FSH pulsatility are not altered by central noradrenergic blockade.
中枢去甲肾上腺素能机制可能参与多囊卵巢综合征（PCO）女性促性腺激素脉冲式分泌的调节。为了验证这种可能性，我们对10名患有PCO的年轻女性进行了如下研究：在基础状态下以及静脉输注α1-肾上腺素能受体拮抗剂百里胺（10微克/千克×分钟）的过程中，每隔10分钟测量一次血清促黄体生成素（LH）、促卵泡生成素（FSH）和催乳素（PRL）的浓度，每隔60分钟测量一次总睾酮和17β-雌二醇的浓度，持续8小时。在输注百里胺期间，血清LH的平均浓度、积分浓度以及LH脉冲频率均无显著变化（P=无显著性差异）。然而，我们发现，在α1-肾上腺素能阻滞期间，LH脉冲幅度出现增加，净增量（P<0.002）和百分比增量（P<0.002）均如此，同时LH平均峰值也增加（P<0.05）。在这些实验条件下，FSH和PRL的脉冲式分泌以及性腺甾体激素均无显著变化。这些数据表明，在PCO患者中，1）脑内去甲肾上腺素能机制在调节LH脉冲式分泌频率方面不发挥刺激作用；2）中枢去甲肾上腺素能活性抑制LH脉冲幅度；3）中枢去甲肾上腺素能阻滞不会改变PRL和FSH的脉冲性分泌。
