The influence of dihydroergotamine on adenosine-induced and reactive coronary vasodilation
Tóm tắt
The influence of dihydroergotamine on adenosine-induced and reactive vasodilation after long and short periods of coronary artery occlusion was investigated in thoracotomized dogs. Adenosine-induced vasodilation (intracoronary administration) and vasodilation after long periods of coronary artery occlusion (25–35 beats) were similarly influenced, i.e. decreased by the i.v. administration of 10 μg/kg dihydroergotamine. By contrast vasodilation after short periods of coronary artery occlusion (4–7 beats) tended to be increased. This difference in response is thought to arise from two distinct mechanisms of coronary vasodilation after coronary artery occlusion depending on the duration of the occlusion period. The vasodilation after short periods of coronary artery occlusion possibly corresponds to physiological autoregulation. With longer periods of coronary artery occlusion and additional, consecutive mechanism is called into action.
Tài liệu tham khảo
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