The copper induced modification of duodenal biotransformation reactions in rats during fat deficiency.

The effect of ingested copper on the composition of duodenal postmitochondrial supernatnat fraction (PMS), the aryl hydrocarbon hydroxylase (AHH) and UDPglucuronosyltransferase (GT) activities was analyzed in rats given normal or fat free diets. There were only minor changes in the composition of PMS or in the activities of the measured enzymes when rats received a normal diet. During fat deficiency the phospholipid-protein ratio and the GT activity were markedly increased following 10 mM copper concentration in the drinking water. It is concluded that during fat deficiency copper modifies the structure of the microsomes, as analyzed in the PMS, and that this is reflected in the membrane bound GT activity.