Abstract
The vascular complications of diabetes mellitus have been correlated with enhanced activation of protein kinase C (PKC). LY333531, a specific inhibitor of the β isoform of PKC, was synthesized and was shown to be a competitive reversible inhibitor of PKC β1 and β2, with a half-maximal inhibitory constant of ∼5 nM; this value was one-fiftieth of that for other PKC isoenzymes and one-thousandth of that for non-PKC kinases. When administered orally, LY333531 ameliorated the glomerular filtration rate, albumin excretion rate, and retinal circulation in diabetic rats in a dose-responsive manner, in parallel with its inhibition of PKC activities.