| Autor: |
Frank, Michael W., Harris, Kathleen R., Ahlin, KaLee A., Quinn, Debra, Klocke, Francis J. |
| Rok vydání: |
1995 |
| Předmět: |
|
| Zdroj: |
Journal of the American College of Cardiology. 25(2) |
| ISSN: |
0735-1097 |
| DOI: |
10.1016/0735-1097(95)92542-d |
| Popis: |
Although coronary collateral vessels are known to react to several vasoactive agents, the role of endothelial-derived relaxing factor (EDRF) i unclear, Accordingly, the effects of NW-nitro-L-arginine methyl ester (L-NAME), an agent blocking synthesis of nitric oxide, have been examined in six conscious chronically instrumented dogs. Coronary collaterals were induced in the left circumflex (LC) bed by either ameroid implantation or the repeated brief occlusion technique of Franklin. With the native LC artery occluded, LC pressure distal to the occlusion and flow in the LC bed were measured with a chronically implanted LC catheter and systemically administered microspheres before and after left atrial infusion of L-NAME (10mg/kg):Control (Mean±SEM)L-NAME (Mean±SEM)Aortic Pressure (mm Hg)90±4.1113±51*LC Pressure (mmHg)58±6.647±28Aortic-LC Gradient (mmHg)32±3.366±5.5*LC Flow (ml/min/g)1.41±0.061.05±0.18Collateral Resistance23±2875±15*(Aortic-LC Gradient/LC Flow)*p≤0.01, paired tL-arginine, given following L-NAME, reduced the trans-collateral pressure gradient and resistance. We conclude that EDRF (nitric oxide) exerts a substantial tonic vasodilating effect in coronary collaterals. Disease-induced alterations in endothelial function may compromise collateral perfusion. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
