P物质对大鼠结肠平滑肌细胞钾钙电流的影响  

Effect of substance P on the potassium and calcium currents of colonic smooth muscle cells

作　　者：唐勤彩 罗和生[1] 全晓静[1] 樊菡 余光[1] 

机构地区：[1]武汉大学人民医院消化内科消化系统疾病湖北省重点实验室,430060

出　　处：《中华医学杂志》2015年第30期2483-2486,共4页National Medical Journal of China

摘　　要：目的 研究P物质（SP）对大鼠近端结肠平滑肌细胞大电导钙激活钾通道电流（IBKCa）和L型钙通道电流（ICaL）的影响,探讨其促结肠动力的作用机制.方法 选取健康雄性Wistar大鼠24只,采用RM6240生理信号采集处理系统记录SP对大鼠近端结肠平滑肌肌条收缩的影响;采用全细胞膜片钳技术检测SP对近端结肠平滑肌细胞IBKCa和ICaL的影响.结果 10-7～10-6 mol/L的SP能促进大鼠离体结肠平滑肌纵行肌肌条的自发性紧张性收缩;10-8～10-6mol/L的SP能促进环行肌肌条的自发性收缩（均P ＜0.05）.SP（10-6 mol/L）减低IBKCa,在＋60 mV刺激电压下,施加SP干预后,IBKCa电流密度为（11.71±1.65） pA/pF,较对照组的（14.42 ±2.89） pA/pF明显降低（P＜0.05）;SP（10-mol/L）还增大ICaL,在0 mV刺激电压下,施加SP干预后,ICaL电流密度为（-5.04±0.67）pA/pF,较对照组的（-4.25±0.46）pA/pF明显增大（P＜0.01）.结论 SP能够促进大鼠离体结肠平滑肌肌条的自发性收缩,且呈浓度依赖性.SP减低IBKCa,增大ICaL.可能是SP促胃肠动力的机制之一.Objective To investigate the effect of substance P（SP） on the spontaneous contractile activity of smooth muscle cells,the large-conductance calcium-activated potassium channel currents （IBKCa） and the L-type calcium channel currents （ICaL） in rat smooth muscle cells of the proximal colon.Methods A total of 24 healthy male Wista rats were used in this test.The change of smooth muscle strips spontaneous contraction of rat proximal colon after adding SP was recorded by a physiological signal stystem （RM6240）.The IBKCa and ICaL were measured via the whole cell patch-clamp technique.Results The longitudinal muscle contraction was obviously increased concentration-dependently after adding different concentrations of SP （10-7-10-6 mol/L）,so as the circular muscle while adding SP（10-8-10-6 mol/L） （all P 〈 0.05）.Compared with the control group,IBKCa was decreased after adding SP（10-6mol/L）.Under the stimulating voltage of 60 mY,the IBKCa current density was （11.71 ± 1.65） pA/pF,which was significantly lower compared with the control group （14.42 ± 2.89） pA/pF （P 〈 0.05）.The ICaL was apparently increased.Under the stimulating voltage of 0 mY,the ICaL currents density was （-5.04 ± 0.67） pA/pF,compared with the control group （-4.25 ± 0.46） pA/pF,which was significantly increased （P 〈 0.01）.Conclusions SP can promote the spontaneous contractile activity of colon smooth muscle of rats in vitro.And SP decrease IBKCa representatively while apparently increase ICaL.That is probably one of the mechanism SP regulate the gastrointestinal motility.

关 键 词：P物质 结肠 肌 平滑 钙通道 钾通道 

分 类 号：R57[医药卫生—消化系统]