Gálfi M, Baláspiri L, Tóth R, Pávó I, Csajbók E, László F, Morschl E, Varga Cs, László F A
Department of Biology, Faculty of Juhász Gyula Teacher Training College, University of Szeged, Szeged, Hungary.
Regul Pept. 2003 Nov 15;116(1-3):35-41. doi: 10.1016/s0167-0115(03)00190-3.
The regulation of oxytocin (OT) release by galanin (GAL) at the neurohypophyseal (NH) nerve terminal is not adequately understood. The effect of GAL on the secretion of OT was studied in 13- to 14-day cultures of isolated rat NH tissue. By this time, the hormone content of the medium had become constant. The OT content of the supernatant medium was determined by RIA after a 1- or 2-h incubation. A significantly decreased content of OT was found following incubation with 10(-6)-10(-8) M doses of GAL. Dopamine (DA) and the DA-active drugs apomorphine (APM) and Pro-Lys-Gly (PLG) (10(-6) M in each medium) increased the OT synthesis of NH tissue cultures. This elevation of OT secretion could be blocked by the administration of GAL together with DA, APM or PLG. The DA-blocking effect of GAL was prevented by previous treatment with the GAL receptor antagonist galantid (M15). The results indicate that OT release from the NH is directly influenced by the GAL-ergic system. The GAL-ergic control of OT secretion from NH tissue in rats can occur at the level of the posterior pituitary.
甘丙肽（GAL）对神经垂体（NH）神经末梢催产素（OT）释放的调节作用尚未得到充分了解。在分离的大鼠NH组织的13至14天培养物中研究了GAL对OT分泌的影响。此时，培养基中的激素含量已变得恒定。孵育1或2小时后，通过放射免疫分析（RIA）测定上清培养基中的OT含量。在用10（-6）-10（-8）M剂量的GAL孵育后，发现OT含量显著降低。多巴胺（DA）以及具有DA活性的药物阿扑吗啡（APM）和脯氨酸-赖氨酸-甘氨酸（PLG）（每种培养基中为10（-6）M）增加了NH组织培养物中OT的合成。与DA、APM或PLG一起给予GAL可阻断OT分泌的这种升高。GAL的DA阻断作用可通过预先用GAL受体拮抗剂加兰肽（M15）处理来预防。结果表明，NH中OT的释放直接受GAL能系统的影响。大鼠NH组织中OT分泌的GAL能控制可发生在垂体后叶水平。
