PGI2 is not a major prostanoid produced by cultured rabbit renal microvascular endothelial cells

The microvasculature is known to be a source of a number of vasoregulatory prostanoids. In the kidney, these prostanoids have been proposed to influence vascular, tubular, and glomerular function. A rapid method for isolation of large numbers of preglomerular renal microvessels (interlobular arteries and afferent arterioles) from the rabbit kidney has recently been developed in this laboratory. In the current report, we describe methods to culture endothelial cells derived from these isolated renal microvessels. Endothelial cells in primary and continuous cultures were grown in monolayers on culture dishes and plates. These cells demonstrated morphology consistent with that described for other endothelial cells in culture including the presence of Weibel-Palade bodies as seen by electron microscopy. The presence of factor VIII immunofluorescence and angiotensin converting-enzyme activity was also observed. The cultured endothelial cells synthesized a number of common prostanoids under in vitro conditions and the hierarchy of biosynthesis was PGE2 greater than PGF2 alpha greater than PGI2 greater than TxA2. The ratio of the in vitro biosynthesis of PGI2:PGE2 was approximately 1:5, as compared with a 3-5:1 ratio seen in freshly isolated intact microvessels. Prostanoid biosynthesis increased in the cultured endothelial cells in the presence of arachidonic acid (1 and 10 microM), A23187 (10 microM), thrombin (5 U/ml), or bradykinin (1 microM) and decreased with mepacrine (10 microM)-or indomethacin (100 microM), suggesting that these cells were metabolically responsive to a variety of prostanoid stimulators and inhibitors. In summary, endothelial cells can be cultured from freshly isolated preglomerular renal microvessels and have the ability to produce a number of vasoregulatory prostanoids under in vitro conditions.(ABSTRACT TRUNCATED AT 250 WORDS)