Enzymatic reduction of beta-ketonitrosamines.
Enzymatic reduction of beta-ketonitrosamines.
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β-酮亚硝胺的酶促还原。
DOI：
10.1093/carcin/4.11.1495
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发表时间：
1983
期刊：
影响因子：
4.7
通讯作者：
Archer,MC
中科院分区：
文献类型：
--
作者：
Boux,LJ;Leung,KH;Sweet,ME;Archer,MC
研究了叙利亚金仓鼠和Sprague-Dawley大鼠肝脏和胰腺细胞质和微粒体对n -亚硝基（2-氧丙基）胺（BOP）和n -亚硝基（2-氧丙基）丙胺（NOPPA）的还原作用。尽管活性取决于所测试的部分和所使用的辅助因子（NADH或NADPH），但所有肝组分都能降低这两种底物。一般情况下，仓鼠肝脏组分的活性高于大鼠肝脏组分，BOP是比NOPPA更好的底物。在胰腺部分中，只有细胞质溶胶表现出还原酶活性。仓鼠细胞液能够利用这两种辅助因子，但大鼠部分只有在NADPH存在时才表现出活性。BOP是胰酶的较好底物，在NADPH存在下，大鼠和仓鼠的胰酶活性大致相等。这些结果表明，胰腺将BOP还原为HPOP不太可能是BOP诱导物种特异性胰腺癌的重要因素。
The reduction of N-nitrosobis(2-oxopropyl)amine (BOP) and N-nitroso(2-oxopropyl)propylamine (NOPPA) by hepatic and pancreatic cytosol and microsomes from Syrian golden hamsters and Sprague-Dawley rats has been examined. All hepatic fractions reduced both substrates, although the activity depended on the fraction tested and the cofactor employed (NADH or NADPH). Generally, hamster hepatic fractions contained higher activity than the rat hepatic fractions and BOP was a better substrate than NOPPA. Of the pancreatic fractions, only cytosol exhibited reductase activity. The hamster cytosol was able to utilise both cofactors, but the rat fraction exhibited activity only when NADPH was present. BOP was the better substrate for the pancreatic enzymes and in the presence of NADPH, the rat and hamster activities were about equal. These results suggest that the pancreatic reduction of BOP to HPOP is unlikely to be a significant factor in the species-specific induction of pancreatic cancer by BOP.