葡萄糖对豚鼠心室肌细胞跨膜离子电流的影响

摘要/Abstract

摘要：

目的观察葡萄糖对豚鼠心室肌细胞膜APD, IK1, IK, ICa-L的影响. 方法采用全细胞膜片技术记录单个豚鼠心室肌细胞膜的动作电位时程和离子电流.比较0、10和20 mmol·L^-1葡萄糖对心室肌细胞跨膜离子电流的作用.结果 (1)与10 mmol·L^-1葡萄糖相比, 0和20mmol·L^-1均可使豚鼠心室肌细胞的APD缩短(P<0.05); (2)在细胞外葡萄糖浓度为10 mmol·L^-1时, 内向整流钾电流IK1的电流密度最大,标准化I-V曲线显示0和20mmol·L^-1葡萄糖均可抑制IK1, 并使I-V曲线左移, 其翻转电位从-72.4移至-64.6 mV; (3)与mmol·L^-1葡萄糖相比, 0和20mmol·L^-1葡萄糖均可增加ICa-L的电流幅度和电流密度.当钳制电位为10 mV, 细胞外葡萄糖浓度为0 mmol·L^-1时, ICa-L的电流密度为(-8.03±0.82)pA/pF(n=8),而10mmol·L^-1和20mmol·L^-1葡萄糖分别使电流密度增加为(-5.45±0.67)pA/pF和(-6.50±0.56)pA/pF; (4)当钳制电压为+70mV,细胞外葡萄糖浓度为0、10和20 mmol·L^-1时,IK的电流密度分别为(18.96±2.86)pA/pF,(8.66±1.87)pA/pF,(15.32±3.12)pA/pF. 结论细胞外不同浓度的葡萄糖可使豚鼠心室肌细胞APD, IK1, IK, ICa-L发生改变. 细胞外葡萄糖浓度为0和20mmol·L^-1对细胞膜离子电流产生相似的影响.

关键词: 葡萄糖, 葡萄糖, 葡萄糖, 钙电流, 钙电流, 钙电流, 钾电流, 钾电流, 钾电流, 膜片钳, 膜片钳, 膜片钳

Abstract: Aim To determine the effects of glucose on APD, IK1, IK, ICa-L of ventricular myocytes in guinea pigs. Methods Whole-cell patch-clamp technique was used to record the changed action potential ionic current induced by glucose of single cell in guinea pig ventricular myocytes, to compare the action of 0, 10 and 20 mmol·L^-1 glucoses on transmembrane ionic current. Results (1) Compared with 10 mmol·L^-1 glucose concentrations, 0 and 20 mmol·L^-1 glucose both shortened APD of ventricular myocytes (P<0.05). (2) The inward components of IK1 density were maximal when the glucose concentration was at 10 mmol·L^-1. Normalized I-V relationships showed that both 0 and 20 mmol·L^-1 glucose produced a left-shift of I-V curve. The reverse potential changed from -72.4 mV to -64.6 mV. (3) Compared with 10 mmol·L^-1, both 0 and 20 mmol·L^-1 glucose markedly increased the ICa-L amplitude and density. The ICa-L current density was (-8.035±0.82) pA/pF (n=8) at a test potential of 10 mV when the glucose concentration was 10 mmol·L^-1. But its current density decreased to (-5.45±0.67) pA/pF and (-6.50±0.56) pA/pF when glucose concentrations were 0 and 20 mmol·L^-1, respectively. (4) The current densities of IK were (18.96±2.86) pA/pF, (8.66±1.87) pA/pF, and (15.32±3.12) pA/pF, at +70 mV for 0, 10 and 20 mmol·L^-1 glucoses, respectively. Conclusion Glucose in different concentrations has different effects on APD, IK1, IK, and ICa-L of single ventricular myocyte in guinea pigs. There are similar actions of 0 and 20 mmol·L-1 glucoses on the transmembrane ionic current of ventricular myocytes in guinea pigs.

Key words: glucose, glucose, calcium channel, calcium channel, potassium channel, potassium channel, patch-clamp technique, patch-clamp technique

中图分类号:

R329.251

R965

Supporting: Foundation item: The Key Fund of the Technological Office of Heilongjiang Province (20010101001-00). The Foundation of the Educational Office of Heilongjiang Province (10531094). National Natural Science Foundation of China (30371647).
^*Corresponding author. Tel.: 86-451-86671354; fax: 86-451-86669482

艾静, 焦军东, 王赫, 杜智敏, 杨宝峰^*. 葡萄糖对豚鼠心室肌细胞跨膜离子电流的影响[J]. .

AI Jing, JIAO Jun-dong, WANG He, DU Zhi-min, YANG Bao-feng^*. Effects of Glucose on Transmembrane Ionic Current of Ventricular Myocytes in Guinea Pig[J]. .

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