Felman K, Tappaz M
INSERM U 171, CNRS UA 1195, Centre Hospitalier Lyon-Sud, Pierre Bénite, France.
Neuroendocrinology. 1989 Jun;49(6):580-5. doi: 10.1159/000125172.
The effect of chronic hyperprolactinemia was studied on (a) GABA concentration in the pituitary anterior lobe; (b) GABA biosynthesis enzyme, glutamate decarboxylase (GAD) activity in the hypothalamic median eminence, and (c) GABA degradation enzyme GABA-transaminase (GABA-T) activity at both levels. In male rats bearing the prolactin-secreting tumor MtTF4 for 1 month or treated for 5 days with estradiol benzoate, the plasma prolactin concentration was markedly increased (between 4- and 10-fold basal values). In both cases, GABA concentration was significantly increased (40-60%) in the anterior pituitary lobe. A slight reduction (20-30%) in GABA-T activity was observed in the anterior lobe while no change in GAD or GABA-T activity was measured in the median eminence. These results are discussed in relationship to a possible feedback input of prolactin on the tuberoinfundibular GABAergic system.
(a)垂体前叶中γ-氨基丁酸（GABA）的浓度；(b)下丘脑正中隆起中GABA生物合成酶谷氨酸脱羧酶（GAD）的活性，以及(c)两个水平上GABA降解酶GABA转氨酶（GABA-T）的活性。在患有分泌催乳素的肿瘤MtTF4达1个月的雄性大鼠或用苯甲酸雌二醇处理5天的雄性大鼠中，血浆催乳素浓度显著升高（为基础值的4至10倍）。在这两种情况下，垂体前叶中的GABA浓度均显著增加（40%至60%）。在前叶中观察到GABA-T活性略有降低（20%至30%），而在正中隆起中未检测到GAD或GABA-T活性的变化。结合催乳素对结节漏斗GABA能系统可能的反馈输入对这些结果进行了讨论。
