Sahu A
Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, PA 15261, USA.
Endocrinology. 1998 Nov;139(11):4739-42. doi: 10.1210/endo.139.11.6432.
Recent evidence suggests that leptin reduces food intake (FI) by acting at the hypothalamic level. Leptin decreases hypothalamic neuropeptide Y (NPY), melanin-concentrating hormone (MCH) and galanin (GAL) gene expression in rats. The purpose of the present study was to test the hypothesis that leptin decreases FI by additionally modulating the action of NPY, MCH or GAL in the hypothalamus. Intracerebroventricular (i.c.v.) administration of NPY, MCH or GAL induced FI in satiated rats. A prior i.c.v. injection of leptin (4 microg) completely prevented the increase of FI either by MCH, GAL or NPY. These results suggest that modulation of post-synaptic actions of MCH, GAL and NPY is one of the mechanisms of leptin signaling in the hypothalamus.
最近的证据表明，瘦素通过作用于下丘脑水平来减少食物摄入量（FI）。瘦素可降低大鼠下丘脑神经肽Y（NPY）、促黑素细胞激素（MCH）和甘丙肽（GAL）的基因表达。本研究的目的是检验以下假设：瘦素通过额外调节下丘脑NPY、MCH或GAL的作用来降低食物摄入量。向饱足的大鼠脑室内（i.c.v.）注射NPY、MCH或GAL可诱导食物摄入量增加。预先脑室内注射瘦素（4微克）可完全阻止由MCH、GAL或NPY引起的食物摄入量增加。这些结果表明，调节MCH、GAL和NPY的突触后作用是瘦素在下丘脑信号传导的机制之一。
