Walz W
Department of Physiology, University of Saskatchewan, Saskatoon, Canada.
Neurosci Biobehav Rev. 1997 Mar;21(2):135-42. doi: 10.1016/s0149-7634(96)00003-6.
The evidence for spreading depression waves between the ischemic core and penumbra and its role in extending the core into the penumbra is reviewed. Experiments from the author's laboratory using primary cultures of astrocytes and intracellular pH and K(+)-sensitive microelectrodes are described. The results suggest a passive involvement of astrocytes during an ischemic process. Neurones react by equilibrating their K+ and Na+ gradients very quickly. The resulting glial depolarization leads to passive Donnan-mediated KCl and water fluxes into astrocytes. Such a mechanism could explain the depolarizing phase of spreading depression. The repolarization phase must involve energy-consuming processes which are probably located in neurones. These processes are still unknown.
本文综述了缺血核心区与半暗带之间扩散性抑制波的证据及其在将核心区扩展至半暗带中的作用。文中描述了作者实验室利用星形胶质细胞原代培养以及细胞内pH和钾离子敏感微电极所做的实验。结果表明，星形胶质细胞在缺血过程中被动参与其中。神经元通过非常迅速地平衡其钾离子和钠离子梯度做出反应。由此产生的胶质细胞去极化导致唐南介导的氯化钾和水被动流入星形胶质细胞。这样一种机制可以解释扩散性抑制的去极化阶段。复极化阶段必定涉及可能位于神经元中的耗能过程。这些过程仍然未知。
