Effect of pyridine on the hepatic and pulmonary metabolism of 2-butanol in rat and rabbit.

Pyridine has been shown to be an effective inducer of the ethanol-inducible cytochrome P-450IIE1 in both liver and lung. The oxidation of 2-butanol by rat liver is inducible by chronic ethanol consumption. The purpose of this study was to determine the effect of pyridine on the hepatic and pulmonary metabolism of butanol. Comparisons were made between rat and rabbit. Acute pyridine treatment (200 mg/kg, ip) increased hepatic metabolism of 2-butanol in the rat twofold and in the rabbit threefold. The effect of pyridine on hepatic butanol oxidase is similar to the effect reported by other investigators for ethanol administered in the drinking water for 3 wk. Control rabbit pulmonary butanol oxidase activity was 10-fold higher than that in the rat. Pyridine decreased pulmonary butanol oxidase activity in the rabbit. The effect was demonstrated both in vitro and in the isolated perfused rabbit lung. Pyridine had no effect on pulmonary butanol oxidase activity in the rat.