6-Keto-PGF 1α Synthesis in Diabetic Rat Aorta: Effect of Substrate Concentration and Cholesterol Feeding

Abstract

The effect of short-term feeding of a 1% cholesterol diet to normal and streptozotocin-induced diabetic rats on aortic 6-keto-PGF_1α synthesis from exogenous and endogenous arachidonic acid (AA) was investigated. Diabetes and cholesterol feeding (by themselves) resulted in a reduction in aortic synthesis of 6-keto-PGF_1α from both exogenous and endogenous arachidonic acid. An additive effect of diabetes and cholesterol feeding together was found for synthesis of 6-keto-PGF_1α from exogenous but not endogenous AA. Experiments in which the AA concentration was varied suggested that the inhibition of aortic 6-keto-PGF_1α synthesis by diabetes was competitive in nature. The diabetic rat was also found to be severely compromised in its ability to handle dietary cholesterol, as evidenced by a dramatic increase in plasma total cholesterol.