线粒体和微粒体谷胱甘肽S-转移酶在大鼠肝脏癌前病变组织中的变化

本文报道在大鼠肝脏化学致癌过程中癌前病变组织的细胞浆、微粒体、线粒体及核膜等亚细胞组分内谷胱甘肽S-转移酶(glutathione S-transferase,GST)活性的变化。在大鼠肝脏癌前病变组织中,胞浆、线粒体及微粒体内,以1,2-二氯-4-硝基苯(1,2-dichloro4-nitrobenzene,DCNB)为底物的A-C组GST活性以及以1-氯-2,4-二硝基苯(1-chlo-ro-24-dinitroben-zene,CDNB)为底物的B组GST活性均显著增高然而在核膜中上述的两种分子形式的GST活性,均无明显变化。实验结果表明,GST不仅存在于胞浆中,而且在线粒体、微粒体及核膜中也固有。把二乙基亚硝胺(diethylnitrosamine,DEN)腹腔注射后给予2-乙酰氨基芴(2-acetylaminofluoren,FAA)并进行肝脏部分切除,以此制造大鼠肝脏癌前病变,这时组织中不仅是胞浆中的GST活性明显升高,而且微粒体和线粒体GST也有显著升高。因此,作者认为微粒体及线粒体GST也可做为肝脏肿瘤标志酶。

Changes in Activities of Mitochondrial and Microsomal Glutathione S-transferases in Rat Hepatocyte Nodules

Changes in activities of mitochondrial, microsomal, cytosolic and nuclear membrane glutathione S-transferases(GST) in rat hepatocyte nodules formed during chemical hepatocarcinogenesis were investigated. In rat hepatocyte nodules both activities of mitochondrial, microsomal cytosolie GST of A-C groups, used with 1-chloro-2,4-dinitrobenzene (DCNB)as a substrates, and GST of B groups, used with 1, 2-dichloro-4-nitrobenzene(CDNB) as a substrates, were markedly increased, while activities of neuclear membrane GST were changed little. These results indicate that GST is found not only in cytosol but also in miotochondria. microsome and nuclear membrane. It is suggested that not only cytosolic GST, but also mitochondrial and microsomal GST an be used as a preneoplastic hepatic marker enzymes.