Eiselt Michael, Giessler Frank, Platzek Dieter, Haueisen Jens, Zwiener Ulrich, Röther Joachim
Institute of Pathophysiology and Pathobiochemistry, Klinikum der Friedrich-Schiller-Universität, D-07740 Jena, Germany.
Brain Res. 2004 Nov 26;1028(1):83-91. doi: 10.1016/j.brainres.2004.09.002.
Spreading depression (SD) propagates in cortical regions that are different in their morphological and functional characteristics. We tested whether the propagation pattern of spreading depression was different between parts of the cortex. In six adult rats, we recorded the ECoG by a 4 x 4 electrode array that covered parts of the frontal, parietal cortex and the cingulate cortex. Simultaneously a 16-channel magnetoencephalogram was recorded to characterize the development and direction of intracortical ion movements accompanying this phenomenon. Spreading depression was initiated by occipital application of 0.3 molar KCl solution. Depolarization was observed, at first, at lateral cortical regions and then at medial cortical regions. Thereafter, the propagation velocity increased in medial cortical regions and was faster than in lateral regions. Negative potential shifts were detected by all electrodes, but the depolarization reached a maximum over lateral and caudal cortical regions. The recorded magnetic fields indicated the same orientation of currents underlying these fields, which was perpendicular to the wave front and points away from the depolarization region. Overall, the data indicated that propagation patterns of spreading depression differed between parts of the cortex and, thus, propagation was inhomogeneous. This propagation was accompanied by strong currents parallel to the cortical surface.
扩散性抑制（SD）在形态和功能特征各异的皮质区域中传播。我们测试了皮质不同部位之间扩散性抑制的传播模式是否存在差异。在六只成年大鼠中，我们通过一个覆盖额叶、顶叶皮质和扣带回皮质部分区域的4×4电极阵列记录了皮层脑电图（ECoG）。同时记录了16通道脑磁图，以表征伴随此现象的皮质内离子运动的发展和方向。通过枕部应用0.3摩尔氯化钾溶液引发扩散性抑制。首先在皮质外侧区域观察到去极化，随后在内侧皮质区域观察到。此后，内侧皮质区域的传播速度增加，且比外侧区域更快。所有电极均检测到负电位偏移，但去极化在外侧和尾侧皮质区域达到最大值。记录的磁场表明这些场下的电流具有相同的方向，该方向垂直于波前并指向远离去极化区域的方向。总体而言，数据表明扩散性抑制的传播模式在皮质不同部位之间存在差异，因此传播是不均匀的。这种传播伴随着与皮质表面平行的强电流。
