Mager R, Ferroni S, Schubert P
Max Planck Institute for Psychiatry, Department of Neuromorphology, Martinsried, F.R.G.
Brain Res. 1990 Nov 5;532(1-2):58-62. doi: 10.1016/0006-8993(90)91741-x.
Whole cell currents were recorded in cultured rat hippocampal neurons using the patch-clamp method. When the cells were held near the resting membrane potential (-60 mV) the application of adenosine (1 microM) or the adenosine analogues 2CA (100 nM) and R-PIA (40 nM) induced a steady-state inward current. This response was unchanged when extra- and intracellular media were used, in which Na+ and K+ were substituted by impermeable ions in equimolar concentrations. In contrast the current was affected by lowering the extracellular Cl- concentration and thus Cl- was considered to be the ionic carrier. Additionally an almost complete block of the current was observed after applications of DIDS (50 microM), a putative Cl- channel blocker. The modulated current was voltage-dependent and was slowly activated by hyperpolarizing voltage steps. The adenosine action was theophylline- and pertussis toxin-sensitive indicating that the modulatory effect is mediated via an A1 receptor coupled to a G protein of the Gi or Go class.
采用膜片钳方法在培养的大鼠海马神经元中记录全细胞电流。当细胞保持在静息膜电位（-60 mV）附近时，施加腺苷（1 μM）或腺苷类似物2CA（100 nM）和R-PIA（40 nM）会诱导出稳态内向电流。当使用细胞外和细胞内培养基时，这种反应没有变化，其中Na⁺和K⁺被等摩尔浓度的不可渗透离子替代。相反，电流受到细胞外Cl⁻浓度降低的影响，因此Cl⁻被认为是离子载体。此外，在应用DIDS（50 μM）（一种假定的Cl⁻通道阻滞剂）后，观察到电流几乎完全被阻断。调制电流是电压依赖性的，并且通过超极化电压阶跃缓慢激活。腺苷的作用对茶碱和百日咳毒素敏感，表明调节作用是通过与Gi或Go类G蛋白偶联的A1受体介导的。
