SWELLING-INDUCED CHANGES IN ELECTROPHYSIOLOGICAL PROPERTIES OF CULTURED ASTROCYTES AND OLIGODENDROCYTES .1. EFFECTS ON MEMBRANE-POTENTIALS, INPUT IMPEDANCE AND CELL-CELL COUPLING
SWELLING-INDUCED CHANGES IN ELECTROPHYSIOLOGICAL PROPERTIES OF CULTURED ASTROCYTES AND OLIGODENDROCYTES .1. EFFECTS ON MEMBRANE-POTENTIALS, INPUT IMPEDANCE AND CELL-CELL COUPLING
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DOI：
10.1016/0006-8993(90)90835-y
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发表时间：
1990-10-08
期刊：
影响因子：
2.9
通讯作者：
KETTENMANN, H
中科院分区：
文献类型：
--
作者：
KIMELBERG, HK;KETTENMANN, H
我们研究了培养的少突胶质细胞和星形胶质细胞在沐浴溶液渗透压变化过程中的膜电位反应。当更换为低渗透压或高渗透压介质时，少突胶质细胞会出现去极化或超极化反应，分别与细胞内 [K+] 的稀释度或浓度一致。星形胶质细胞在高渗介质中以类似的超极化反应，这可以通过细胞内 [K+] 的增加来解释。然而，在低渗介质中，观察到星形胶质细胞更大的去极化。这些数据表明，与少突胶质细胞相反，星形胶质细胞的肿胀会激活特定的通道，这可能与体积控制有关。单细胞的双刺穿研究用于测量中等低渗性对细胞输入阻力的影响，而相邻细胞的双刺穿研究用于测量细胞间耦合的变化。在少突胶质细胞中，发现表观细胞输入电阻和电耦合增加。在培养的星形胶质细胞中，当培养物暴露于所检测的最低培养基渗透压（-100 mM NaCl）时，表观细胞输入电阻没有变化，但细胞间电耦合明显降低。然而，由于细胞间电耦合对通过向单个细胞注入电流来测量膜阻抗的不可避免的贡献，表观细胞电阻变化的缺乏可能是由于细胞间耦合的抵消变化造成的。
We have studied the membrane potential responses of cultured oligodendrocytes and astrocytes during changes in the osmolarity of the bathing solution. Oligodendrocytes responded with a de- or hyperpolarization when changing to hypo- or hyperosmolar medium, consistent with dilution or concentration of intracellular [K+], respectively. Astrocytes responded with a similar hyperpolarization in hyperosmolar medium that could be explained by an increase in intracellular [K+]. In hypoosmolar medium, however, a much larger depolarization of astrocytes was observed. These data imply that in astrocytes, in contrast to oligodendrocytes, swelling activates specific channels, which might be involved in volume control. Dual-impalement studies in single cells were used to measure effects of medium hypotonicity on cell input resistance, while dual-impalement studies on neighboring cells were used to measure changes in cell-cell coupling. In oligodendrocytes an increase in apparent cell input resistance and electrical coupling was found. In cultured astrocytes there was no change in apparent cell input resistance but an apparent decrease in cell-cell electrical coupling when cultures were exposed to the lowest medium osmolarity examined (-100 mM NaCl). However, because of the unavoidable contribution of cell-cell electrical coupling to the measurement of membrane impedance by current injection into a single cell a lack of change in apparent cell resistance could be due to offsetting changes in cell-cell coupling.