Prostanoids and thromboxane production by renal brush border membrane

It has been estimated that proximal tubule are responsible for about 7.5% of total kidney prostaglandin PGE2 production. In the present report we investigated the production of prostanoids and thromboxane by rabbit renal proximal tubule brush border membrane. PGF2 alpha was the major endogenous prostaglandin produced under basal condition. The addition of exogenous arachidonic acid increased only PGE2 production. No PGE2 production was found when vesicles were incubated with indomethacin or at 4 degrees C, suggesting the involvement of the PGH2 synthase and PGE2 isomerase enzymes. Addition of angiotensin II at 10(-6) and 10(-9) mol l-1 did not affect the endogenous PGE2 production by brush border membrane. Thus, results of our study demonstrates that the renal proximal tubule brush border membrane has the capacity to produce prostanoids and thromboxane.