GASTRIC METABOLISM OF ETHANOL IN SYRIAN GOLDEN-HAMSTER

First-pass metabolism (FPM) of orally ingested alcohol has been attrib uted to gastric alcohol dehydrogenase (ADH) activity in both humans an d rats. To determine whether gastric alcohol dehydrogenase is essentia l for alcohol FPM, we sought a species lacking this enzyme. We found t hat Syrian golden hamsters have negligible gastric ADH yet alcohol. FP M (265 +/- 25 mg ethanol/kg) was comparable to that of rats (251 +/- 3 1 mg/kg), To determine whether hamster gastric mucosal cells metaboliz e sufficient alcohol to account for this FPM, primary cultures were es tablished, and these cells metabolized 1.99 +/- 0.84 mu mol ethanol/10 (6) cells/hr, an amount sufficient to account for the bulk of alcohol FPM. In contrast to alcohol dehydrogenase, catalase activity in hamste r gastric mucosa (870 +/- 93 units/g tissue) was eightfold higher than in rat gastric mucosa (111 +/- 9 units/g tissue; P < 0.0001). FPM in hamsters treated with 3-aminotriazole was reduced from 242 +/- 24 to 1 30 +/- 22 mg/kg (P < 0.05) but was not reduced in rats. The results im ply that catalase participates in gastric alcohol metabolism of hamste rs.