Keizer J, D'Agostino G, Nagel R, Volpe T, Gnemi P, Vittozzi L
Department of Comparative Toxicology and Ecotoxicology, Istituto Superiore di Sanità, Rome, Italy.
Sci Total Environ. 1995 Oct 27;171(1-3):213-20. doi: 10.1016/0048-9697(95)04687-0.
The in vitro hepatic metabolism of diazinon, as well as the sensitivity of the brain acetylcholine esterase, to diazoxon inhibitory action have been studied in order to explain the different toxicity of diazinon to Oncorhynchus mykiss (rainbow trout), Poecilia reticulata (guppy), Brachydanio rerio (zebra fish) and Cyprinus carpio (carp). In spite of a very sensitive acetylcholine esterase the carp is very resistant to diazinon toxicity because of its very low rate of bioactivation and relatively high activity of detoxicating enzymes. The trout is very sensitive towards diazinon in spite of its low activity of bioactivation, because of its lack of detoxicating enzymes and a very sensitive acetylcholine esterase. Diazinon is very toxic for the guppy, because this fish combines a relatively sensitive acetylcholine esterase with a high rate of bioactivation. The zebra fish has the most insensitive acetylcholine esterase, associated with a limited activation rate, thus resulting a rather resistant species. The results obtained indicate that diazinon toxicity differences among the fish species studied can largely be explained in relation to metabolic balances in the liver and with the features of the target enzyme.
为了解释二嗪农对虹鳟、孔雀鱼、斑马鱼和鲤鱼的不同毒性，研究了二嗪农的体外肝脏代谢以及脑乙酰胆碱酯酶对二嗪磷抑制作用的敏感性。尽管鲤鱼的乙酰胆碱酯酶非常敏感，但由于其生物活化率极低且解毒酶活性相对较高，所以对二嗪农毒性具有很强的抗性。尽管虹鳟的生物活化活性较低，但由于其缺乏解毒酶且乙酰胆碱酯酶非常敏感，所以对二嗪农非常敏感。二嗪农对孔雀鱼毒性很强，因为这种鱼的乙酰胆碱酯酶相对敏感且生物活化率很高。斑马鱼的乙酰胆碱酯酶最不敏感，且活化率有限，因此是一种相当抗性的物种。所得结果表明，所研究鱼类物种之间二嗪农毒性差异在很大程度上可以根据肝脏中的代谢平衡以及靶酶的特性来解释。
