In vivo studies of carnitine and fatty acid metabolism: Problems with use of anesthetics

Abstract

The use of ether anesthesia as a technique for obtaining liver tissue and plasma from living rats was compared to decapitation followed by in situ sample freezing. Parameters associated with fatty acid metabolism were examined to demonstrate differences in the two methodologies. Use of ether in fasted rats was associated with lower plasma free fatty acids and acetoacetate concentrations, as well as decreased hepatic total carnitine, carnitine, and acid-soluble acylcarnitine content when compared to decapitated animals. No qualitative differences between the ether and decapitated groups were noted, and the quantitative differences observed were consistent with effects induced by the anesthetic. Thus, with respect to in vivo studies of fatty acid metabolism use of anesthetic agents may induce significant changes without providing advantages over decapitation and in situ freezing.