Villa R F, Gorini A
Institute of Pharmacology, Faculty of Science, University of Pavia, Italy.
Neurochem Res. 1991 Oct;16(10):1125-32. doi: 10.1007/BF00966590.
The maximum rates (Vmax) of some mitochondrial enzyme activities related to energy transduction (citrate synthase, malate dehydrogenase, NADH cytochrome c reductase, cytochrome oxidase) and amino acid metabolism (glutamate dehydrogenase) were evaluated in non-synaptic (free) and synaptic mitochondria from rat hippocampus and striatum. Three types of mitochondria were isolated from control rats aged 4, 8, 12, 16, 20 and 24 months and treated ones with L-acetylcarnitine (100 mg.kg-1, i.p., 60 min). Enzyme activities of non-synaptic and synaptic mitochondria are different in hippocampus and striatum, confirming that a different metabolic machinery exists in various types of brain mitochondria. During aging, enzyme activities behave quite similarly in both areas. In vivo administration of L-acetylcarnitine decreased the enzyme activities related to Krebs' cycle mainly of synaptic mitochondria, suggesting a specific subcellular trigger site of action. The drug increased cytochrome oxidase activity of synaptic and non-synaptic mitochondria, indicating the specificity of molecular interaction with this enzyme.
在来自大鼠海马体和纹状体的非突触（游离）线粒体和突触线粒体中，评估了一些与能量转导相关的线粒体酶活性（柠檬酸合酶、苹果酸脱氢酶、NADH细胞色素c还原酶、细胞色素氧化酶）以及氨基酸代谢（谷氨酸脱氢酶）的最大速率（Vmax）。从4、8、12、16、20和24月龄的对照大鼠中分离出三种类型的线粒体，并对用L-乙酰肉碱（100mg·kg-1，腹腔注射，60分钟）处理的大鼠进行分离。海马体和纹状体中非突触线粒体和突触线粒体的酶活性不同，这证实了不同类型的脑线粒体中存在不同的代谢机制。在衰老过程中，两个区域的酶活性表现非常相似。L-乙酰肉碱的体内给药主要降低了突触线粒体中与三羧酸循环相关的酶活性，表明存在特定的亚细胞作用触发位点。该药物增加了突触线粒体和非突触线粒体的细胞色素氧化酶活性，表明与该酶分子相互作用的特异性。
