Marselos M, Strom S C, Michalopoulos G
Department of Pharmacology, Medical School, University of Ioannina, Greece.
Cell Biol Toxicol. 1986 Jun;2(2):257-69. doi: 10.1007/BF00122694.
Aldehyde dehydrogenase was measured in primary cultures of hepatocytes obtained with a two-step collagenase perfusion either from human hepatic tissue or from livers of Fisher rats. Basal enzyme activity declines gradually as a function of time in culture, but remains at all times higher when measured with propionaldehyde and NAD (P/NAD) than with benzaldehyde and NADP (B/NADP). Treatment of the cultures with 2 microM of 3-methylcholanthrene for four days significantly increased the B-NADP activity of human and rat hepatocytes (tenfold and eightfold respectively). In human hepatocytes 3-methylcholanthrene increases also the P/NAD activity, but to a lesser extent (twofold), compared to the B/NADP activity. Due to the significant enhancement of B/NADP activity in cultures of human and rat hepatocytes after application of 3-methylcholanthrene, the initial difference in the basal activity levels between the P/NAD and B/NADP forms diminishes or, in the case of human hepatocytes, is even inverted. These results show for the first time that aldehyde dehydrogenase activity is increased in cultured human hepatocytes. This biochemical property is preserved in human and rat hepatocyte cultures, despite the rather quick loss of the basal aldehyde dehydrogenase activity.
采用两步胶原酶灌注法从人肝组织或 Fisher 大鼠肝脏获取原代肝细胞培养物，测定其中的醛脱氢酶。随着培养时间的推移，基础酶活性逐渐下降，但与用苯甲醛和烟酰胺腺嘌呤二核苷酸磷酸（B/NADP）测定相比，用丙醛和烟酰胺腺嘌呤二核苷酸（P/NAD）测定时，基础酶活性始终更高。用 2 微摩尔的 3-甲基胆蒽处理培养物 4 天，可显著提高人肝细胞和大鼠肝细胞的 B-NADP 活性（分别提高 10 倍和 8 倍）。在人肝细胞中，3-甲基胆蒽也会提高 P/NAD 活性，但与 B/NADP 活性相比，提高幅度较小（两倍）。由于应用 3-甲基胆蒽后人肝细胞和大鼠肝细胞培养物中 B/NADP 活性显著增强，P/NAD 和 B/NADP 形式的基础活性水平最初的差异减小，对于人肝细胞而言，这种差异甚至发生逆转。这些结果首次表明，培养的人肝细胞中醛脱氢酶活性增加。尽管基础醛脱氢酶活性相当迅速地丧失，但这种生化特性在人肝细胞和大鼠肝细胞培养物中得以保留。
