【摘要】 目的 观察δ阿片受体激动剂DPDPE对NG108-15细胞膜上延迟整流钾通道的调节作用。方法 将NG108-15细胞膜电位钳制在-90 mV,给予时程为150 ms的阶跃脉冲刺激,由-50 mV逐渐增至+80 mV,每次递增10 mV,记录到一系列外向延迟整流钾电流,记录给予不同浓度δ阿片受体激动剂DPDPE前后的钾电流变化,比较其作用与给药浓度的关系,同时观察阿片受体拮抗剂纳洛酮（NAL）和特异性δ阿片受体拮抗剂纳曲酮（NTI）对δ阿片受体激动剂DPDPE的阻断效应。结果 δ阿片受体激动剂DPDPE在高浓度(≥10^-6mol/L)时,对钾通道产生兴奋性作用;而低浓度(≤10^-7mol/L)时,对延迟整流钾通道产生抑制作用,且作用均随着时间的延长而逐渐增强。结论δ阿片受体激动剂DPDPE对延迟整流钾通道的作用具有双向调节作用。更多还原

【Abstract】 Objective To investigate the dual effects by the 8 opioid receptor agonists DPDPE on the delayed rectified potassium channels in NG108-15 cells. Methods A series of outward currents were evoked in NG108-15 cells by depolarizing voltage from-50 mV to + 80 mV at holding potential of -90 mV. These currents were delayed rectified potassium currents. Relatively selected 8 opioid receptor agonists DPDPE of higher and lower concentrations were used to modulate the delayed rectified K+ current in NG108-15 cells. Opioid receptor antagonist Naloxone （NAL） and relatively selected 8 opioid receptor antagonist Naltrindole （NTI） were used in the present experiments for the characterization of the actions of opioid receptors. Results The relatively higher concentrations of 8 opioid receptor agonist DPDPE (≥10^-6mol/L) significantly increased the amplitude of the delayed rectified K+ current. On the contrary, the relatively lower concentrations of DPDPE (≤ 10^-12mol/L) decreased the amplitude of the delayed rectified K+ current （P < 0.05）. Furthemore both the increase and decrease were time-dependent. Conclusions δ opioid receptor agonist has dual regulatory effects on the delayed rectified potassium channels in NG108-15 cells.更多还原