Prostanoid biosynthesis in cultured rabbit renal microvascular smooth muscle cells. Effect of arachidonic acid, calcium, and A23187.

It is known that prostanoids are local regulators of vascular tone. Since Ca2+ is known to stimulate prostanoid biosynthesis, we examined this interaction in cultured smooth muscle cells derived from rabbit renal preglomerular microvessels by methods developed in this laboratory. These cells produced prostaglandin (PG)I2, PGE2, PGF2 alpha, and thromboxane A2 under in vitro conditions and biosynthesis was augmented in response to arachidonic acid, A23187, and Ca2+, and diminished in the presence of either mepacrine, aspirin, indomethacin, or meclofenamate. These data indicated that smooth muscle cells cultured in this laboratory were metabolically active and the data suggested that the effect of Ca2+ may be modulated by vasodilator prostanoids produced by the smooth muscle cells. These data failed to explain the greater ratio of the production of PGI2:PGE2 observed in freshly isolated rabbit renal preglomerular microvessels when compared with that seen in cultured endothelial cells derived from the same tissue which was previously reported by this laboratory.