An overview of the biochemical pharmacology of probucol.

Probucol was effective in lowering serum total cholesterol in mice at dietary livels as low as 0.0075%. It was also effective after a single 100 mg/kg I.V. dose in mice. The incorporation of acetate-(14)C into liver lipids of rats and mice was not significantly affected by probucol, although the results, especially in mice, make it impossible to rule out such an effect. Cholesterol absorption was estimated in rats using a dual isotope technique. The observed reductions were not statistically significant. Several liver enzyme activities were determined after probucol treatment in rats, and a significant elevation (32%) was observed in only one, glutamic dehydrogenase. Serum cholesterol was lowered markedly in cholesterol-fed cynomolgus monkeys by probucol. There was no effect on the excretion of neutral steroids and the observed increase in fecal bile acids after drug treatment could not be confirmed statistically.