【摘要】 乙醇是心脏抑制剂 ,有明显的降低心肌收缩的作用。神经递质乙酰胆硷 (ACh)调节心脏功能的最重要的离子通道是经鸟苷酸调节蛋白 (G蛋白 )的 βγ亚单位而激活的毒蕈碱型钾通道 (IK,ACh)。作者采用全细胞膜片钳的方法观察了豚鼠心房肌细胞乙酰胆硷激活的钾通道及乙醇对其影响。乙醇对 IK,ACh的抑制呈剂量依赖性效应 ,灌注之后可使 ACh激活的 IK,ACh速率减慢 ,峰值下降。乙醇可抑制 IK,ACh,从而影响副交感神经对心脏的调节作用。更多还原

【Abstract】 Ethanol is a cardiac depress and it can inhibit the contraction of cardiac muscles. Acetylcholine (ACh) released from parasympathetic nerves binds to muscarinic (M 2) ACh receptor (mAChR) in the heart and this leads to the activation of muscarinic K + channel via the βγ subunit of a G protein. The muscarinic K + channel (I K,ACh ) in guinea pig atrial cells and the effect of an alcohol (ethanol) on I K,ACh were investigated using the whole cell patch clamp technique. Ethanol depressed I K,ACh in a dosedependent manner and ethanol slowed activation of I K,ACh and reduced peak I K,ACh . The decrease of I K,ACh by ethanol may impair parasympathetic control of the heart.更多还原