摘要
目的:研究长期抑制酪氨酸激酶活性对胰岛β细胞中电压依赖性钙通道的影响,探讨酪氨酸激酶在胰岛β细胞中的作用。方法:原代培养小鼠胰岛和胰岛β细胞,经0.1mmol/L酪氨酸激酶抑制剂木黄酮处理12h后,运用全细胞电流记录的方法观察电压依赖性钙电流以及动作电位的改变,RT PCR方法观察电压依赖性钙通道α1亚单位的表达改变。结果:木黄酮处理12h后,小鼠胰岛β细胞的电压依赖性钙电流明显减小(13.83±1.515pA/pF vs7.012±1.502pA/pF,P<0.01,n=6),动作电位幅度明显减弱(38.50±7.46mVvs15.95±4.39mV,P<0.01,n=6)。木黄酮处理12h后,小鼠胰岛中电压依赖性钙通道的α1亚单位的表达明显减少,降低为对照组的0.792±0.078(P<0.01,n=5)。结论:木黄酮处理可以抑制小鼠胰岛β细胞中电压依赖性钙通道的表达和电流,提示长期抑制酪氨酸激酶活性在胰岛β细胞功能损害中具有重要作用。
Aim: To determine the effect of long-term inactivation of tyrosine kinases on voltage-gated calcium currents in pancreatic β-cells and to evaluate the function of tyrosine kinases in pancreatic β-cells. Methods: Primarily cultured mouse pancreatic islets and β-cells were pretreated by 0.1 mmol/L genistein for 12 hours. Voltage-gated calcium currents and action potentials were recorded with patch clamp techniques in the configuration of perforated whole-cell recording. RT-PCR method was used to evaluate the changes in expression of voltage-gated calcium channels α1 subunit. Results: After treatment by genistein for 12 hours, the whole-cell voltage-gated calcium currents were significantly diminished(-13.83±1.515 pA/pF vs -7.012±1.502 pA/pF, P<0.01, n=6). The amplitudes of action potentials in genistein-treated β-cells were also significantly attenuated (38.50±7.46 mV vs 15.95±4.39 mV,P<0.01, n=6). The expression of voltage-gated calcium channels α1 subunit in mouse islets was significantly decreased to 0.792±(0.078) of that in control conditions (P<0.01,n=5). Conclusion: Genistein treatment decreases expression and current of voltage-ga-(ted) calcium currents in mouse pancreatic β-cells, which suggests that inhibition of tyrosine kinases activity plays an important role in the dysfunction of pancreatic β-cells.
出处
《中国应用生理学杂志》
CAS
CSCD
北大核心
2005年第2期206-210,共5页
Chinese Journal of Applied Physiology
