RESUMO
<p><b>AIM</b>To observe the effects of urea on ECG and sodium currents of ventricular myocyte in mice.</p><p><b>METHODS</b>ECG and patch clamp techniques were used in the experiments, to record ECG of mice and sodium currents of ventricular myocyte in mice.</p><p><b>RESULTS</b>Urea could lead mice heart rate evidently slow down (P < 0.01) with concentration dependent. The heart rate were (556 +/- 29, 469 +/- 37, 378 +/- 48) b minT in low, middle, high groups respectively before using urea and (612 +/- 27, 615 +/- 23, 619 +/- 26) x min(-1) after. The conduction block arrhythmia was happened in middle and high groups. The sodium currents of ventricular myocyte in mice was inhibited by urea(P < 0.05). The sodium currents amplitude value were reduced to (7.32 +/- 0.68, 5.69 +/- 0.64, 4.58 +/- 0.57) nA after using urea in each group and were (8.76 +/- 0.91, 8.87 +/- 1.01, 8.77 +/- 0.96) nA before, submit concentration dependent.</p><p><b>CONCLUSION</b>Urea can inhibit the sodium currents of ventricular myocyte in mice to make it happen conduction block arrhythmia.</p>