[Effect of urotensin II on iNOS expression in human umbilical vein endothelial cells].

AIM: To observe the direct effect of urotensin II (U II) on the release of nitric oxide (NO) and expression of inducible nitric oxide synthase (iNOS) mRNA in human umbilical vein endothelial cells (HUVEC). METHODS: HUVEC were cultured with different concentrations of U II (10(-9)-10(-7) mol/L) for 24 hours. Then the supernatant was collected to detect the level of NO and the activity of iNOS, the expression of iNOS mRNA of HUVEC was measured by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: In comparison with controls, the level of NO, the activity of iNOS and the iNOS mRNA expression increased significantly (P < 0.05). CONCLUSION: U II may up-regulate the expression of iNOS mRNA and increase NO generation in HUVEC, it suggests that U II may relax blood vessel by activating iNOS/NO pathway.