Abstract
The effects of 3-morpholinosydnonimine (SIN-1) were studied in isolated canine basilar arteries. Rings with and without endothelium were suspended in Krebs-Ringer bicarbonate solution bubbled with 95% O2-5% CO2. Changes in isometric force were recorded. SIN-1, nitric oxide, and sodium nitroprusside caused concentration-dependent relaxations of control preparation contracted by uridine-5'-triphosphate. The removal of endothelium augmented the relaxation to the nitrovasodilators. Increasing concentrations of SIN-1 reduced endothelium-dependent contractions to the calcium ionophore A23127 and arachidonic acid. The results of the present study suggest that SIN-1 causes relaxation and prevents endothelium-dependent contractions in cerebral arteries. The inhibitory effect of SIN-1 is reduced by the presence of endothelium possibly by interaction with endothelium-derived relaxing factors and/or superoxide anions produced in endothelial cells. The inhibition of endothelium-dependent contractions could be due in part to chemical interactions between endothelium-derived contracting factor (superoxide anion) and the nitric oxide liberated by SIN-1.
Original language | English (US) |
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Pages (from-to) | S72-S75 |
Journal | Journal of Cardiovascular Pharmacology |
Volume | 14 |
DOIs | |
State | Published - 1989 |
Keywords
- Canine basilar arteries
- Endothelium-derived relaxing factors
- Nitric oxide
- Nitrovasodilators
- SIN-1
- Sodium nitroprusside
ASJC Scopus subject areas
- Pharmacology
- Cardiology and Cardiovascular Medicine