Detoxification Strategies of Two Types of Spiders Revealed by Cypermethrin Application

In order to compare the detoxification capacities of two species of spiders, Linyphia triangularis and Pardosa prativaga were exposed to a commonly used pesticide, cypermethrin (a chlorinated pyrethroid). Two detoxification enzyme systems — glutathione S-transferase (GST) and glutathione peroxidase (GSH-Px) — were assayed as biomarkers. The two species of spiders have different life-styles and eat different food, and in our experiment were at different stages of their life-cycle. Therefore, differences in detoxification strategies could be expected. From our results, we suggest two different strategies. L. triangularis had a generally high basal level of GST, which could be further induced by exposure to cypermethrin. The basal activity of GSH-Px was relatively low, and no response to toxic exposure could be traced. Thus, this enzyme plays only a minor role in the detoxification process of cypermethrin in L. triangularis. In P. prativaga, a low basal GST activity was found. However, the basal level of GSH-Px was comparable to that of L. triangularis. A significant rise in GSH-Px activity (with t-butyl-hydroxyperoxide as substrate) was apparent 12 hours after exposure. This may indicate that P450 enzyme systems are involved in the cypermethrin metabolising process in P. prativaga. In addition, GSH-Px activity (with H₂O₂ as substrate) could be traced in P. prativaga but not in L. triangularis, indicating that a true peroxidase system is active in P. prativaga.