Barski D, Zasadowski A
Division of Veterinary and Environmental Toxicology, Department of Pathology and Pharmacology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego 14, 10-719 Olsztyn, Poland.
Pol J Vet Sci. 2006;9(1):43-9.
The study was aimed at determining the dimethoate residues in the liver and acetylcholinesterase (AChE) activity in blood of rats exposed to dimethoate (individual intoxication), and dimethoate and pyrantel embonate (simultaneous intoxication). The experiment was carried out in two stages where various doses of preparations and exposure manners were used. In the first stage of the experiment, dimethoate (1/25 LD50) was administered to animals per os for 28 days, and pyrantel embonate (1/2 LD550) twice, i.e. on the day 14th and 28th. In the second stage, dimethoate was administered for 5 days (1/10 LD50), and pyrantel embonate (1/5 LD50) on day 3, 4 and 5 from the beginning of dimethoate intoxication. The short presence of the dimethoate residues in the liver of the animals examined was found until the 2nd day after 28-day intoxication (1/25 LD50) and until 14th day after 5-day intoxication (1/10 LD50), however, a distinct decrease in this insecticide residues in the liver of (analysed groups of) rats occurred between the 3rd hour and the 2nd day after exposure. Dimethoate in both applied doses significantly reduced AChE activity in blood. After application of the higher dose, the inhibition of AChE was more pronounced, and the return of its activity to physiological values lasted considerably longer. Co-administration of pyrantel embonate and dimethoate, slightly influenced changes of the parameters analysed, which have been dependent not only on a dose and manner of pyrantel application but also on time which lapsed from exposure.
该研究旨在测定暴露于乐果（个体中毒）、乐果与噻嘧啶（同时中毒）的大鼠肝脏中的乐果残留量以及血液中的乙酰胆碱酯酶（AChE）活性。实验分两个阶段进行，采用了不同剂量的制剂和暴露方式。在实验的第一阶段，给动物经口灌胃乐果（1/25 LD50），持续28天，噻嘧啶（1/2 LD550）给药两次，即分别在第14天和第28天。在第二阶段，乐果给药5天（1/10 LD50），噻嘧啶（1/5 LD50）在乐果中毒开始后的第3天、第4天和第5天给药。在28天中毒（1/25 LD50）后的第2天之前以及5天中毒（1/10 LD50）后的第14天之前，在所检查动物的肝脏中均发现有乐果残留，但在暴露后的第3小时至第2天之间，（所分析组的）大鼠肝脏中的这种杀虫剂残留量明显下降。两种给药剂量的乐果均显著降低了血液中的AChE活性。给予较高剂量后，AChE的抑制作用更明显，其活性恢复到生理值的持续时间也长得多。噻嘧啶与乐果联合给药对所分析参数的变化有轻微影响，这些变化不仅取决于噻嘧啶的给药剂量和方式，还取决于暴露后经过的时间。
