羟苯氨酮激活家兔血管平滑肌细胞钙敏感钾通道

Activation of Ca²⁺-activated K⁺ channels by oxyphenamone in rabbit mesenteric vascular smooth muscle cells

摘要: 目的研究羟苯氨酮(oxyphenamone,Oxy)扩张血管作用机理。方法用全细胞膜片钳技术,监测家兔肠系膜阻力血管平滑肌细胞钙敏感钾通道电流变化以及Oxy对其的影响。结果0.1 μmol·L^-1 Oxy明显增加钙敏感钾通道电流,冲洗后恢复至给药前水平;0.01～10 μmol·L^-1 Oxy明显增加钙敏感钾通道电流,且呈现浓度依赖性。结论 Oxy呈浓度依赖性和可逆性的增大血管平滑肌细胞钙敏感钾通道电流。

Abstract: AimTo study the effects of oxyphenamone (Oxy) on activation of Ca²⁺-activated K⁺ channels in rabbit mesenteric vascular smooth muscle cells. MethodsTo measure the effect of Oxy on the Ca²⁺-activated K⁺ channel (BK (Ca) channel) activity in rabbit mesenteric vascular smooth muscle cells by using whole cell patch clamp techniques. ResultsOxy reversibly increase BK (Ca) channel activity in rabbit mesenteric artery smooth muscle cells. Application of Oxy (0.1 μmol·L^-1) to the perfusion solution caused significant increase in outward currents and its effect was completely abolished by washout; The outward currents K⁺ was inhibited by TEA (7.5 mmol·L^-1); Oxy activated the BK (Ca) channel in a dose-dependent manner (0.01-10 μmol·L^-1). ConclusionOxy directly increase the activity of BK (Ca) channel activity in rabbit mesenteric vascular smooth muscle cells in dose-dependent manner.