Vasoactive hormones induce nitric oxide synthase mRNA expression and nitric oxide production in human endothelial cells and monocytes

Isoform-2 nitric oxide synthase (NOS-2) mRNA expression and nitric:oxide (N O) production are induced in endothelial cells and monocytes by cytokines s uch as gamma IFN and LPS. We evaluated NOS-2 and isoform-3 NOS (NOS-3) mRNA expression and NO production in human monocytes and human umbilical vein e ndothelial cells:(HUVEC), under basal conditions and after incubation with physiologic concentrations of vasoactive hormones. NOS mRNA expression was detected by reverse transcription polymerase chain reaction (RT-PCR) and NO production by electronic paramagnetic resonance spectroscopy (EPR). We sho wed that NOS-2 mRNA expression and NO production were induced by stimulatio n with epinephrine, dopamine,: endothelin-l, and angiotensin II, both in mo nocytes and HUVEC. NOS-3 mRNA expression and NO production were detected un der basal conditions in monocytes and HUVEC:and were not modified by the pr esence of vasoactive hormones. Human endothelial cells and monocytes expres s the NOS-2 and NOS-3 mRNA and the inducible NOS-2 mRNA expression increase s after vasoactive hormone stimulation. (C) 1999 American Journal of Hypert ension, Ltd.