Effects of cold stress and ether stress on aminopyrine demethylation kinetics in vivo

Abstract

Abstract The effect of cold stress and ether stress on mixed function oxidase activity in vivo has been studied using the aminopyrine-−14CO2 exhalation rate (CER) method. Cold stress following both acute and chronic exposure resulted in enhanced rate of demethylation of both aminopyrine (CER α half-life) and its monomethyl metabolite (CER β half-life). However the time course of the response to cold stress differs for the two demethylations. The characteristics of the cold-induced enhancement of aminopyrine-CER would appear to differ in several aspects from that reported for phenobarbitone pretreatment. In contrast, ether exposure did not produce any consistent effect on drug metabolizing status of the rat.