The Effects of Aminoethyl Phosphonic Acid on Hepatic Microsomal Drug Metabolism and Ultrastructure of Normal and Cholesterol Fed Rats

The effects of parenteral administration of aminoethyl phosphonic acid (AEP) on the liver microsomal drug metabolism and ultrastructure were studied in normal and 1% cholesterol-fed albino rats. AEP administration to rats fed a stock-diet resulted in decreased demethylation of aminopyrine with a concomitant fall in cytochrome P-450 level. Aniline hydroxylation remained unaltered. AEP injection to cholesterol-fed rats, caused marked reduction in both aminopyrine demethylation and aniline hydroxylation, with a significant increase in cytochrome P-450 level. AEP injection to both control and cholesterol-fed animals produced a modest increase in Bilirubin UDP-glucuronyl transferase. RNA:DNA ratio showed remarkable elevation in rats fed the cholesterol diet with AEP injection. AEP injection caused an atypical smooth endoplasmic reticulum and a marked loss of nuclear euchromatin. Effect of AEP was more pronounced in rats receiving the cholesterol-diet. AEP administration thus induces structural and drug metabolic enzyme alteration in liver.