microsomal ethanol oxidizing system
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microsomal ethanol oxidizing system(mī″krō-sōm′āl),
A hepatic enzyme system that catabolizes drugs and other potentially toxic substances. Ethanol ingested in relatively small amounts is catabolized by the hepatic enzyme alcohol dehydrogenase. Whenever ingested amounts of ethanol are large enough to overcome or deplete the alcohol dehydrogenase system, the MEOS becomes the major route for ethanol catabolism. Ethanol breakdown by the MEOS is not thought to produce as much energy as alcohol dehydrogenase breakdown, resulting in less weight gain than would be expected from the ethanol calories consumed.