高脂食物喂饲大鼠后的下丘脑核团神经元形态变化

Morphometric Analysis of Hypothalamic Nucleus in the Rats on a Short-term High Cholesterol Diet

将１２只大鼠分为实验组和对照组，每组６只动物。实验组用高脂食物喂饲，对照组用基础食物喂饲，４个月后，取下丘脑，用体视学方法分析了下丘脑视前内侧核和腹内侧核神经元的形态变化参数。结果发现这两个核团的神经元数目实验组比对照组明显减少，而细胞体积增大。光镜下检查主动脉管壁，发现实验组均有局部增厚，弹性膜及平滑肌排列疏松；电镜发现内皮下有胶原纤维和平滑细胞增生。血清总胆固醇实验组也明显高于对照组。本文并对用高脂食物喂饲大鼠后，下丘脑血管调控中枢神经元出现形态变化的可能机理进行了初步分析。

Twelve rats were divided into two groups.One group was given high cbolesterol diet andthe other group was given basal diet for four months. The morphological changes in the neu-rons of medial preoptic and ventromedial nuclei of hypothalamus of both groups were anal-ysed morphometrically. The results showed that thae number of neurons in the above mentioned nuclei showed significant reduction in the experimental group when compared withthose of the controls, but the average volume of the meurons was greater,Atherosclerosiswas evidenced by local thickning of the vessel wall and loose arrangement of elastic fibersandsmooth muscles under light microscope,and increased number of smooth muscle cells andcollagenous fibers in the aorta under electron microscope,Plasma cholesterol level in chole-terol-fed rats was higher than that in controls. The results of this study indcates that the va-soregulatory centre in the hypothalamus of rats undergoes morphological changes obviouslyafter being fed with high cholesterol diet for four months.The mechanism of these changesrequires further study.