Nademanee K, Lockhart E, Pruitt C, Singh B N
Department of Cardiology, Wadsworth Veterans Administration Hospital, Los Angeles, CA 90073.
J Cardiovasc Pharmacol. 1987;10 Suppl 3:S81-5.
The hypotensive effects of ketanserin, a selective blocker of 5-hydroxytryptamine2, are well defined, but its electrophysiologic effects in humans are not. Intravenous ketanserin (0.15 mg/kg) was therefore given to 10 patients undergoing electrophysiologic evaluation, and data were obtained before and after drug administration. The mean ketanserin plasma level was 389 +/- 211 ng/ml. Ketanserin decreased systolic and diastolic blood pressure, but the change did not reach statistical significance. Ketanserin increased the QTc interval by 3% (p less than 0.01), without effect on QRS or the HV intervals. Ketanserin exerted no effect on ventricular effective refractory period (ERP) but decreased the atrial ERP by 6% (p less than 0.01); the decrease in atrioventricular (AV) nodal ERP and in the AV nodal Wenkebach cycle length did not reach statistical significance. The sinus node recovery time and intranodal conduction time were shortened significantly by ketanserin. The data indicate that ketanserin has a modest effect in prolonging ventricular repolarization without influencing the fast sodium channel. Its effect on atrial refractoriness and on sinus and AV-nodal function suggests a complex interaction with the autonomic nervous system in producing its net cardiac electrophysiologic actions.
酮色林是一种5-羟色胺2的选择性阻滞剂，其降压作用已得到明确，但对人体的电生理作用尚不明确。因此，对10例接受电生理评估的患者静脉注射酮色林（0.15mg/kg），并在给药前后获取数据。酮色林的平均血浆水平为389±211ng/ml。酮色林可降低收缩压和舒张压，但变化未达到统计学意义。酮色林使QTc间期延长3%（p<0.01），对QRS或HV间期无影响。酮色林对心室有效不应期（ERP）无影响，但使心房ERP降低6%（p<0.01）；房室（AV）结ERP和AV结文氏周期长度的降低未达到统计学意义。酮色林可显著缩短窦房结恢复时间和结内传导时间。数据表明，酮色林在不影响快钠通道的情况下，对延长心室复极有适度作用。其对心房不应期以及窦房结和房室结功能的影响表明，在产生其净心脏电生理作用时，与自主神经系统存在复杂的相互作用。
