CHOLESTEROL LOWERING EFFECT OF RHEUM RIBS IN HYPERCHOLESTEROLEMIC RABBITS

The effects of ethanolic and aqueous extracts of Rheum ribs L. (RR) of the family polygonaceae was studied on serum cholesterol concentration in rabbits. To induce hypercholesterolemia, 0.5 g/kg/day of pure cholesterol powder was given orally to each rabbit for two weeks then cholesterol was halved and each group of animals was treated with a different regimen for another two weeks. Both the ethanolic and the aqueous extracts significantly decreased serum cholesterol conc-entration. The ethanolic extract decreased serum cholesterol by the end of the first and the second week by 43.9% and 59.1% (both p<0.001) respectively while the cholesterol reduction with aqueous extract was 25.01% (p<0.05) and 43.82% (p<0.0 1) at the end of the first and the second week of treatment respectively. The ethanolic extract was found to be more potent than the aqueous one. When comp- ared with nicotinic acid as a positive control, the hypocholesterolemic effect of ethanolic extract was significantly higher than that of nicotinic acid. Therefore, we may conclude that RR extracts have hypocholesterolemic effect and thus can be used in the treatment of hypercholesterolemia which is the major risk factor of cor-onary heart disease (CHD).