Responses of Glutathione S-transferase and Glutathione Peroxidases to Feeding Rate of a Wolf Spider Pardosa prativaga

Søren Achim Nielsen and Søren Toft

Groups of large juvenile wolf spiders (Pardosa prativaga) were kept on constant Drosophila melanogaster rations of 0 (starvation), 1, 2, 3.5, 7, 14 or 28 flies per week, or ad libitum feeding. After 3–4 weeks, they were sacrificed and the activities of three biomarker enzyme systems — glutathione S-transferase (GST) with chlorodinitrobenzene as substrate, glutathione peroxidase with H2O2 as substrate (GSH-Px[H2O2]), or glutathione peroxidase with tbutyl-hydroperoxide as substrate (GSH-Px[TBH]) — were assayed. Two systems (GST and GSH-Px[H2O2]) showed decreasing enzyme activity with increasing feeding rate, whereas the variation in GSH-Px(TBH) was independent of feeding rate. Sex and body weight had no influence on enzyme activity.