Optical analyses of ischemic dysfunction in cortex-hippocampus neural networks using membrane potential images

（1）神经刺激的传播被光学记录在吉尔比海马体和皮质切片中，该切片因潜在敏感的荧光染料而死亡， RH 414。当Hippocampal CA 1地区的Schaffer collaterals被电刺激时，膜分离的传播扩展到两种stratum radiatum和stratum oriens。在恶性切片中，神经元刺激被刺激到第四层的轴向第二层，然后在同一层上扩展。（2）长期的神经元分化也被观察到在德国大脑切片中，准备了18-20小时后4分钟过渡性非线性硬化。当Schaffer collaterals被刺激时，神经元分化的范围仅在stratum radium中传播，以及神经元刺激对stratum金字塔和stratum orians的传播被抑制。因此，神经元功能失调可能已经在过渡性疾病发生后18-20小时，although degeneration of pyramidal neurons未找到. 3） The cortical spreading depression which was evoked by high-ky D1刺激没有显著影响到the extent of neuronal depolarization evoked by electric stimulation in cortical slices.4） Gerbils预处理或不处理2分钟的forebrain ischemia（前条件）被限制在急性贫血症5分钟内。神经刺激的传播在没有预条件的情况下得到了改善，并在对照那些来自非条件的情况下得到了比较。Hence，“预条件可能导致对功能性生理神经损伤的容忍”。

1) The propagation of neuronal excitation was optically recorded in gerbil hippocampal and cortical slices which were dyed with a potential sensitive fluorescence dye, RH 414. When the Schaffer collaterals of hippocampal CA1 region were electrically stimulated, the propagation of membrane depolarization extended to both stratum radiatum and stratum oriens. In cortical slices, neuronal excitation evoked by a stimulation onto the layer IV axially propagated to the layer II, and then extended over the same layer.2) The extent of neuronal depolarization was also observed in gerbil brain slices which were prepared 18-20 hr after 4 min of transient forebrain ischemia. When the Schaffer collaterals were stimulated, the extent of neuronal depolarization spread only within the stratum radiatum and the propagation of neuronal excitation to the stratum pyramidale and stratum oriens was inhibited. Thus, neuronal dysfunction might already occur 18-20 hr after the transient ischemia, although degeneration of pyramidal neurons was not found.3) The cortical spreading depression which was evoked by high-KィイD1+ィエD1 stimulation did not significantly affect to the extent of neuronal depolarization evoked by electrical stimulation in cortical slices.4) Gerbils pre-treated with or without 2 min of forebrain ischemia (pre-conditioning) were insulted to 5 min of forebrain ischemia. The propagation of neuronal excitation was improved in hippocampal slices from pre-conditioned gerbils in comparison with those from gerbils without pre-conditioning. Hence, the pre-conditioning may induce the tolerance against functional ischemic neuronal damages.