脾气虚模型大鼠海马与下丘脑神经元线粒体分裂因子和线粒体分裂蛋白1的表达

Expression of Mitochondrial Fission Factor and Mitochondrial Fission Protein 1 in Hippocampus and Hypothalamic Neurons of Pi-qi Deficiency Model Rats

目的观察脾气虚模型大鼠海马、下丘脑神经元线粒体形态学变化及其分裂情况,探讨脾气虚的发生机制。方法 20只SPF级雄性SD大鼠随机分为非脾气虚组和脾气虚模型组,每组10只。脾气虚模型组采用饮食失节+劳倦方法制脾气虚模型。透射电镜观察海马CA1区及下丘脑神经元线粒体的形态学变化;ELISA法检测海马和下丘脑组织ATP含量;Western blot法检测上述组织线粒体分裂因子(MFF)和线粒体分裂蛋白1(Fis1)的表达。结果非脾气虚组线粒体较丰富,形态基本正常,而脾气虚模型组线粒体数量减少,其中海马CA1区神经元线粒体出现肿胀、嵴减少,甚至空泡化,而下丘脑还存在较多线粒体自噬现象。与非脾气虚组比较,脾气虚模型组体重、进食量、饮水量、运动距离、站立次数以及前肢抓力均下降,海马和下丘脑神经元ATP含量降低,MFF及Fis1蛋白表达升高(P<0.05,P<0.01)。结论海马和下丘脑相关神经元线粒体功能低下及其促分裂成分表达增加与脾气虚的发生密切相关。

Objective To observe changes of mitochondrial morphology and fission of hippocam- pal and hypothalamic neurons in Pi-qi deficiency rats, explore the mechanism of Pi-qi deficiency. Methods Twenty male SD rats of SPF level were randomly divided into the non Pi-qi deficiency group and the Pi-qi deficiency group, 10 in each group. The Pi-qi deficiency group used the method of eating dislocation and laboriness to make the Pi-qi deficiency model. Transmission electron microscopy was used to observe mitochondrial morphologic changes of hippocampal CA1 area and hypothalamic neurons. The level of ATP in hippocampal and hypothalamic tissues were measured by ELISA. The expressions of mitochondrial fis- sion factor（MFF） and mitochondrial fission protein 1 （Fisl） in these tissues were detected by Western blot. Results The mitochondria of the non Pi-qi deficiency group were abundant and the morphology was normal. The number of mitochondria in the Pi-qi deficiency group decreased, the mitochondria of the hipp- ocampal CA1 area neurons were swollen, the cristae decreased and even vacuolated, and there were more mitochondrial autophagy in the hypothalamus. Compared with the non Pi-qi deficiency group, the body weight, food intake, drinking water, exercise distance, standing frequency and forelimb grasping force in the Pi-qi deficiency group decreased （P 〈0.05, P 〈0.01 ）. The level of ATP in both hippocampal and hypothalamic tissues in the Pi-qi deficiency group were markedly less than those in the non Pi-qi defi- ciency group（all P 〈0.01 ）. However, MFF and Fisl expressions in the Pi-qi deficiency group were signifi- cantly higher than those in the non Pi-qi deficiency group （P 〈0.05, P 〈0.01 ）. Conclusion The reduc- tion of hippocampal and hypothalamic mitochondrial function and elevated expressions of promoting mito- chondrial fission components are closely related to the occurrence of Pi-qi deficiency.