McGowan M K, Andrews K M, Grossman S P
Committee on Biopsychology, University of Chicago, IL 60643.
Physiol Behav. 1992 Apr;51(4):753-66. doi: 10.1016/0031-9384(92)90112-f.
In Experiment 1, one-week infusion of insulin (0.15, 1.5, or 15.0 microU/hr) into the ventromedial hypothalamus (VMH) of rats reduced body weight (BW) and nighttime food intake (FI). While 0.15 microU/h decreased daytime FI, 1.5 microU/h increased daytime FI and 15.0 microU/h left daytime FI unchanged. Total daily FI was decreased by the two highest doses. In Experiment 2, intra-VMH infusion of specific insulin antibodies (1.5 microUeq/h) increased BW and FI, while C-peptide antibodies were ineffective. In Experiment 3a, intracerebroventricular infusions of insulin failed to decrease FI and BW comparably to similar intrahypothalamic infusions. In Experiment 3b, intra-VMH insulin was infused via cannulae that bypassed the cerebral ventricles. The decrease in FI and BW was comparable to that observed when insulin was infused via cannulae that penetrated a ventricle. Histology from animals used in Experiments 1-3 indicates that optimum sites for insulin-induced changes in BW and FI in the hypothalamus lie in an area that includes portions of the paraventricular, arcuate, dorsomedial, and ventromedial nuclei.
在实验1中，向大鼠腹内侧下丘脑（VMH）持续一周输注胰岛素（0.15、1.5或15.0微单位/小时）可降低体重（BW）和夜间食物摄入量（FI）。虽然0.15微单位/小时可降低白天的食物摄入量，但1.5微单位/小时会增加白天的食物摄入量，而15.0微单位/小时使白天的食物摄入量保持不变。最高的两个剂量可降低每日总食物摄入量。在实验2中，向VMH内输注特异性胰岛素抗体（1.5微单位当量/小时）可增加体重和食物摄入量，而C肽抗体则无效。在实验3a中，脑室内输注胰岛素未能像类似的下丘脑内输注那样降低食物摄入量和体重。在实验3b中，通过绕过脑室的套管向VMH内输注胰岛素。食物摄入量和体重的降低与通过穿透脑室的套管输注胰岛素时观察到的情况相当。实验1至3中所用动物的组织学检查表明，胰岛素引起下丘脑体重和食物摄入量变化的最佳部位位于一个包含室旁核、弓状核、背内侧核和腹内侧核部分的区域。
