Halothane depletes cardiac microvasculature enzymes in the rat

Left ventricular arterioles from Sprague-Dawley rats were analyzed histochemically to determine the effects of halothane administration on key enzymes of aerobic and anaerobic metabolism, as well as on key enzymes of the hexose monophosphate shunt. Significant decreases occurred in cytochrome oxidase (-42%) and beta-hydroxybutyrate dehydrogenase (-57%). No significant changes were observed in isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, or lactate dehydrogenase. These data suggest that anesthetic levels of halothane can cause impaired metabolism in the coronary microvasculature.