Background. Verapamil is an effective vasodilator. The purpose of this study was to investigate the in vivo effect of verapamil on coronary blood flow velocity and vascular resistance in anesthetized, open-chest rabbits. Methods. Twenty-one male New Zealand white rabbits were anesthetized, and a 3-mm suction-type pulsed Doppler velocimeter probe was applied to the proximal part of the left anterior descending coronary artery after median sternotomy. The rabbits received intravenous bolus infusion of 4 different doses of verapamil (0.01 mg/kg, n = 5; 0.1 mg/kg, n = 5; 1 mg/kg, n = 5, and 10 mg/kg, n = 6). The percent changes in coronary blood flow velocity and coronary vascular resistance were examined. Results. There was 10.0 ± 1.6% increase in coronary blood flow (CBF) and 12.5 ± 1.9% reduction in coronary vascular resistance (CVR) after infusion of 0.01 mg/kg of verapamil. The CBF increased 23.0 ± 9.5% and CVR decreased 24.2 ± 5.2% after infusion of 0.1 mg/kg of verapamil. Infusion of 1 mg/kg of verapamil induced 34.8 ± 10.5% increase in CBF and 32.6 ± 2.5% reduction in CVR. The CBF increased 41.1 ± 14.8% and CVR decreased 45.1 ± 5.4% after infusion of 10 mg/kg of verapamil. Conclusions. Compared with baseline condition, all doses of verapamil increased coronary blood flow velocity and decreased coronary vascular resistance significantly in anesthetized, open-chest rabbits.
|Number of pages||6|
|Journal||Chinese Medical Journal (Taipei)|
|Publication status||Published - 2001|
- Coronary vasodilatation
- Pulsed doppler velocimetry
ASJC Scopus subject areas