维甲酸对亚硝胺诱发大鼠肝癌的阻断作用

二乙基亚硝胺（ＤＥＮ）诱发大鼠肝癌过程中，可使肝中增殖指标γ－谷氨酰转肽酶（γ－ＧＴ），谷胱甘肽Ｓ－转移酶（ＧＳＴ），胞液和膜性酪氨酸蛋白激酶（ｃ－ＴＰＫ，ｍ－ＴＰＫ）有不同程度的逐步升高，直至１６周（除ｃ－ＴＰＫ在第１２周活力最高外），而分化指标精氨酸酶（ＡＧＮ）则明显降低，如在诱癌开始的同时给予全反式维甲酸（ＲＡ）连续１６周则可延缓γ－ＧＴ、ＧＳＴ和两种ＴＰＫ的升高和ＡＧＮ的降低，这种作用并非ＲＡ本身对酶活力的影响，而是ＲＡ阻断肝癌发展的结果。

Blocking Effect of Retinoic Acid on N-Nitrosodiethylamine Induced Rat Liver Carcinoma

During the development of induced rat hepatocarcinoma by N-nitrosodiethylamine(DEN), the liver proliferative indexes including γ-glutamyltranspeptidase(γ-GT), glutathione Stransferase (GST), cytosolic and membranous tyrosine protein kinase (c-TPK, m-TPK) were gradually increased in various degrees up to 16 weeks,except c-TPK was highest in 12th week of carcinogenesis, and the liver differentiative index, arginase, was decreased significantly. If all-trans retinoic acid (RA) was administrated at the beginning of liver cancer induction with DEN and prolonged for 16 weeks, the increase of γ-GT, GST and both TPKs as well as the decrease of AGN were all slowed down. These effects were not caused by RA itself acting directly on enzyme activities,but were due to the blocking effect of RA on the development of liver carcinogenesis.