Cold stress offered modulation on chlorpyrifos toxicity in aging rat central nervous system

The adverse effects produced by chlorpyrifos (CPF) or cold stress alone in humans and animals are well documented, but there is no information available relating to the consequences of their co- exposure in an age-related manner. In this study, effects of sublethal doses of CPF were carried out in vivo, for 48 h to assess the biochemical perturbations in relation to interactions with cold stress (15°C and 20°C) in different age group rat CNS. A positive interaction of CPF with age of animal and cold exposure was observed resulting in marked decrease in the activity levels of AChE (P<0.05), ChAT (P<0.05), Na(+), K(+)-ATPase (P<0.05), Ca(2+)-ATPase (P<0.05), and Mg(2+)-ATPase (P<0.05). The ANOVA and posthoc analysis showed that regulatory enzymes decreased significantly (P<0.05) on CPF exposure. Overall, the effect of co-exposure was appreciably different from either of the exposures. Synergistic interaction of CPF and cold stress at 15°C showed higher inhibition in comparison with CPF and cold stress alone and together at 20°C. Further, this study reveals that young animals are significantly vulnerable and sensitive than adults.