Beverly J L, Martin R J
Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.
Physiol Behav. 1991 Feb;49(2):295-9. doi: 10.1016/0031-9384(91)90046-q.
Activity of the GABA-synthesizing enzyme, glutamate decarboxylase (GAD), was measured in brain areas involved in glucoregulation 60 min after a glucoprivie challenge. The rate of GAD activity in the ventromedial nucleus of the hypothalamus (VMN) increased in a dose-dependent manner in response to intraperitoneal injection of 2-deoxy-D-glucose (2-DG). The increase in VMN GAD activity was significantly correlated with an increase in food intake (r2 = .77, p less than 0.01). The increase in VMN GAD activity was not due to the higher food intake since rats receiving 2-DG and denied access to food also had elevated rates of VMN GAD activity. VMN GAD activity was increased 28% and 32% after intracerebroventricular injection of 2-DG or 5-thioglucose, respectively. The rates of GAD activity in the lateral hypothalamus and area postrema were not affected by either peripherally or centrally administered 2-DG. The increase in VMN GAD activity after glucoprivation may be involved in the regulation of blood glucose by influencing food intake.
在进行糖剥夺刺激60分钟后，对参与葡萄糖调节的脑区中γ-氨基丁酸（GABA）合成酶谷氨酸脱羧酶（GAD）的活性进行了测定。腹腔注射2-脱氧-D-葡萄糖（2-DG）后，下丘脑腹内侧核（VMN）中的GAD活性速率呈剂量依赖性增加。VMN中GAD活性的增加与食物摄入量的增加显著相关（r2 = 0.77，p < 0.01）。VMN中GAD活性的增加并非由于食物摄入量增加，因为接受2-DG且无法获取食物的大鼠VMN中GAD活性速率也有所升高。脑室内注射2-DG或5-硫代葡萄糖后，VMN中GAD活性分别增加了28%和32%。外侧下丘脑和最后区中GAD的活性速率不受外周或中枢给予2-DG的影响。糖剥夺后VMN中GAD活性的增加可能通过影响食物摄入量参与血糖调节。
