摘要
目的:研究一种具有生长激素释放活性的脑肠肽(Ghrelin)对大鼠心室肌细胞L型钙电流的影响。方法:采用酶解消化法获得大鼠单个心室肌细胞,通过全细胞膜片钳技术研究不同浓度(10 nmol/L、100 nmol/L及1μmol/L)Ghrelin对L型钙电流的影响。结果:10 nmol/L、100 nmol/L及1μmol/L Ghrelin依次抑制大鼠心室肌细胞L型钙电流峰电位,抑制率分别为:8.95%±2.13%、31.18%±4.78%及64.63%±8.57%,(P<0.05);I-V曲线上移,通道半数失活电压从(-1.34±1.9)mV分别降至(-8.04±1.32)mV、(9.76±1.17)mV及(-11.81±0.73)mV(P<0.05),并延长失活后恢复时间由给药前τ值63.23±9.32,分别增至98.95±10.74、109.56±13.42和127.39±16.13,差异有统计学意义(P<0.05)。结论:Ghrelin通过加快L型钙电流的失活及延长失活后恢复时间,具有浓度依赖性地抑制L型钙电流。
Objective： To study the effect of ghrelin on L-type calcium channel current （ICa-L） of ventricular myocytes in experimental rats. Methods： The single ventricular myocyte in experimental rats were obtained by enzymolysis method, and the whole-cell patch-clamp technique was used to investigate the effect of ghrelin on ICa-L of ventricular myocytes at different doses of 10 nmol/L, 100 nmol/L and 1μmol/L respectively. Results： Ghrelin at 10 nmol/L, 100 nmol/L and 1μmol/L may inhibit ICa-L at （8.95 ± 2.13） %, （31.18 ± 4.78） % and （64.63 ± 8.57）% respectively,P〈0.05, and the current-voltage curve was shifted upwards. The channel half inactivation curve decreased from （-1.34 ± 1.9） mV to （-8.04 ± 1.32 ） mV, （9.76 ± 1.17） mV and （-11.81 ± 0.73） mV respectively,P〈0.05, and the recovery time after inactivation was prolonged as τ value from （63.23 ± 9.32） to （98.95 ± 10.74）, （109.56 ± 13.42） and （127.39 ± 16.13） respectively,P〈0.05. Conclusion： Ghrelin may accelerate ICa-L inactivation and prolong the recovery time after inactivation. Ghrelin inhibits ICa-L in a dose-dependent manner.
出处
《中国循环杂志》
CSCD
北大核心
2014年第10期832-835,共4页
Chinese Circulation Journal
关键词
L-型钙电流
全细胞膜片钳技术
Ghrelin
L-type calcium channel
Whole-cell patch-clamp
