Regulation of Myocardial Prostaglandin Dehydrogenase Activity. The Role of Cyclic 3′,5′-AMP and Calcium Ions

Summary

A prostaglandin dehydrogenase (sp act, 15 units/mg protein) was isolated from the canine myocardium. The enzyme oxidized the 15-hydroxy group of most prostaglandins tested except for PGBs and PGA₂ which were poor substrates. It required NAD and intact sulfhydryl groups. Its activity was enhanced by cyclic 3′,5′-AMP at low concentrations (10^-10 to 10^-7 M) and inhibited by CaCl_2. The significance of these findings for the control of myocardial prostaglandin levels is discussed.