氢化可的松琥珀酸钠对人和豚鼠心肌细胞钠电流的影响氢化可的松琥珀酸钠对人和豚鼠心肌细胞钠电流的影响

目的研究氢化可的松琥珀酸钠对人心房肌细胞和豚鼠心室肌细胞钠电流的影响。方法应用酶解法分离单个心肌细胞,应用全细胞膜片钳技术记录氢化可的松琥珀酸钠对钠电流的作用。结果氢化可的松琥珀酸钠(1,3,10 μmol·L^-1)浓度依赖性地抑制人心房肌细胞和豚鼠心室肌细胞钠电流,IC₅₀分别为6.97和8.74 μmol·L^-1。氢化可的松琥珀酸钠不改变i_Na的最大激活电压。氢化可的松琥珀酸钠对钠电流的抑制作用起效快,见于用药后1～3 min。结论氢化可的松琥珀酸钠浓度依赖性地抑制钠电流,此作用出现快,提示可能与非基因组效应有关。

Effects of hydrocortisone sodium succinate on sodium current in human and guinea pig cardiac myocytes

AIM: To study the effects of hydrocortisone sodium succinate on sodium current in human atrial myocytes and in guinea pig ventricular myocytes. METHODS: Single cardiac myocytes were isolated by enzyme. The effects of hydrocortisone sodium succinate on sodium current (INa) were assessed by applying whole-cell patch clamp techniques. RESULTS: Hydrocortisone sodium succinate (1, 3, 10 micromol x L(-1)) was shown to inhibit INa of both human atrial myocytes and guinea pig ventricular myocytes in concentration dependent manner and the IC50 were 6.97 and 8.74 micromol x L(-1), respectively. The inhibition effects acted quickly (1-3 min) and the maximal activating voltage of INa was not changed in both human and guinea pig cardiac myocytes. CONCLUSION: Hydrocortisone sodium succinate can exhibit inhibitory effects on INa in both human and guinea pig cardiac myocytes, and its inhibitory effects act rapidly, which are not consistent with genomic effects, so there may be nongenomic effects.