Effects of propofol on ATP sensitive K~+ currents in human atrial myocytes / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of different doses of propofor on ATP-sensitive K~+currents(I_KATP)in human atrial myocytes and the underlying mechsnism.Methods A small piece of myocardiumwas obtained from right atrium in patients undergoing atrial septal defect or ventricular septal defect surgery.Themyocardium specimen was placed in cold Ca~(2+)-free cardioplegic solution aerated with 100% oxygen.Themyocardium specimen was cut into small chunks(1 mm~3).Atrial myocytes were isolated by enzymatic dissociationtechnique.The effects of propofol on I_KATP in atrial myocytes were studied using the whole-cell configuration ofpatch-clamp technique.Results The outward currents were recorded with a pipitte solution containing 0.3mmol?L~(-1) ATP.The currents were inhibited by glibendamide 10 ?mol?L~(-1),a specific K_ATP channel inhibitor,suggesting that the outward currents were I_KATP.I_KATP aws activited by propofol in a dose-dependent manner.Conclusion Propefol can activate the I_KATP in human myocytes in a concentration-dependent manner and themechanism of its myocardial depressant action may be partly explained.