[Expression of inducible nitric oxide synthase in atherosclerotic rabbits]

Atherosclerotic lesions contain vascular smooth cells and thus may have an increased capacity for generation of nitric oxide (NO) by inducible NO synthase (iNOS). Rabbits (n = 8) were raised for eight weeks by the atherogenic diet, then the aortic rings were captured. Contractive responsiveness to norepinephrine, changes of CGMP, expression of iNOS of aortic rings were examined in vitro. There was a substantial decrease in contractile responsiveness to norepinephrine (NE) (P < 0.05), a decrease of CGMP (P < 0.01) and an increase of expression of iNOS (P < 0.05), after L-arginine or sodium nitroprusside treatment. The contractile responsiveness to NE was attenuated (P < 0.01). The CGMP was increased ((P < 0.01). After NG-nitric arginine (L-NNA) treatment, those reaction were reversed. It implied that L-arginine/NO pathway obstructure might likely be another mechanism of atherosclerosis and atherosclerotic arteries and had an increased capacity for generation of NO by iNOS.