Different responses of mesenteric artery from normotensive and spontaneously hypertensive rats to nitric oxide and its redox congeners
Abstract
The conversion of nitric oxide (NO
) into its congeners nitrosonium (NO ) and nitroxyl (HNO/NO) ions may have important consequences for signal transduction and physiological responses. Manganese-containing superoxide dismutase (MnSOD) may convert
NO into its redox congeners. In our current work, we have examined the mechanism of sodium nitroprusside (SNP)-induced relaxation of arteries, with or without endothelium, from both normotensive and spontaneously hypertensive (SH) rats in the absence and
presence of MnSOD. SNP induced a greater degree of relaxation in normotensive than in SH rats. MnSOD antagonized SNPinduced relaxation and effect was greater in normotensive than hypertensive rats. However, MnSOD even potentiated SNP-induced
relaxation in mesenteric arteries with endothelium from SH rats. Our results indicate that HNO/NO-mediated relaxation is more effective in mesenteric artery smooth muscle from SH rats than from normotensive rats and that vascular dysfunction in SH rat...s is not
solely endothelium-derived but involves changes in vascular smooth muscl
Keywords:
Endothelium / Hypertension / Mesenteric artery / MnSOD / Sodium nitroprussideSource:
Pharmacological Report, 2007, 59, 315-322Publisher:
- Springer