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The vasodilator potency of the endothelium-derived relaxing factor, L-S-nitrosocysteine, is impaired in conscious spontaneously hypertensive rats.
- Source :
-
Vascular pharmacology [Vascul Pharmacol] 2006 Jun; Vol. 44 (6), pp. 476-90. Date of Electronic Publication: 2006 May 11. - Publication Year :
- 2006
-
Abstract
- Objective: This study compared the hemodynamic responses elicited by the endothelium-derived relaxing factor (EDRF), L-S-nitrosocysteine (L-SNC), the non-prostanoid EDRF released by acetylcholine (ACh) and nitric oxide (NO)-donors such as MAHMA NONOate, in conscious spontaneously hypertensive (SH) and normotensive Wistar-Kyoto (WKY) rats.<br />Methods: The depressor and/or vasodilator responses elicited by intravenous injections of ACh, L-SNC and MAHMA NONOate were determined in adult WKY and SH rats before and after intravenous injection of the NO synthesis inhibitor, N(G)-nitro-L-arginine methylester (L-NAME), or the cyclooxygenase inhibitor, indomethacin.<br />Results: The responses elicited by ACh and L-SNC were smaller in SH than in WKY rats whereas the responses elicited by MAHMA NONOate were augmented in SH rats. The ACh-induced responses were not diminished after injection of L-NAME in WKY or SH rats. Indomethacin did not affect the responses to any of the vasodilator agents in WKY or SH rats. Addition of L-SNC to whole blood or thoracic aortae from SH rats yielded similar amounts of NO to those of WKY rats.<br />Conclusions: The vasodilator potencies of ACh and L-SNC were diminished whereas that of NO was augmented in SH rats. The loss of potency of L-SNC in SH rats was not obviously due to differences in decomposition to NO or the overactivity of cyclooxygenase factors. This study provides the first evidence that diminished endothelium-dependent vasodilation in SH rats may involve a loss of vasodilator potency of endogenous L-SNC.
- Subjects :
- Acetylcholine pharmacology
Animals
Blood Pressure
Coenzyme A pharmacology
Cysteine pharmacology
Dose-Response Relationship, Drug
Enzyme Inhibitors pharmacology
Femoral Artery enzymology
Femoral Artery physiopathology
Hypertension enzymology
Male
NG-Nitroarginine Methyl Ester pharmacology
Nitric Oxide metabolism
Nitric Oxide Donors pharmacology
Nitric Oxide Synthase antagonists & inhibitors
Nitric Oxide Synthase metabolism
Nitroprusside pharmacology
Rats
Rats, Inbred SHR
Rats, Inbred WKY
Splanchnic Circulation drug effects
Vascular Resistance
Cysteine analogs & derivatives
Femoral Artery drug effects
Hypertension physiopathology
S-Nitrosothiols pharmacology
Vasodilation
Vasodilator Agents pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 1537-1891
- Volume :
- 44
- Issue :
- 6
- Database :
- MEDLINE
- Journal :
- Vascular pharmacology
- Publication Type :
- Academic Journal
- Accession number :
- 16697269
- Full Text :
- https://doi.org/10.1016/j.vph.2006.03.013