Hypolipidemic agents.

Despite the fact that the role of lipids and cholesterol in atherosclerosis has not been totally clarified to the clinician's satisfaction, medicinal chemistry has been very successful in this last decade in showing that a diverse group of compounds is capable of reducing blood lipid levels in many animal species and in humans. The pharmacological basis for the evaluation of many hypolipidemic agents is summarized. The prostaglandins are vasodepressor agents. They inhibit uterine contraction, yet, on the other hand, they increase cardiac output and induce contraction of intestinal smooth muscle. Prostaglandins exhibit marked antilipolytic activity. It has been shown that 0.2 mug/kg/min, of intravenous infusion of prostaglandin E1 produced an increase in serum-free fatty acide levels in the dog. At a 4 times higher rate of infusion, the plasma-free fatty acid concentration was lowered. The pharmacological activities of individual prostaglandins embrace a great variety of biological phenomena. In certain systems their effects are antagonistic. The rationale for the use of estrogens as hypolipidemics is the observation of the low incidence of atherosclerotic heart disease in Caucasian women of childbearing age.