Distribution of Intra- and Extracellular K+ in the Leech Central Nervous System Studied Using Double-Barrelled Ion-Sensitive Microelectrodes
The maintenance of an ionic homeostasis within the central nervous system is undoubtedly essential for proper neuronal functioning in both vertebrates and invertebrates (9, 10). The leech central nervous system has been the subject of many electrophysiological studies at cellular and behavioural levels (2). In the present study we have used double-barrelled K+ -sensitive liquid ion-exchanger microelectrodes to measure intracellular (in the Retzius cell somata) and extracellular K+ activity; also to monitor changes in K+ produced by altering the [K+] of the bathing solution and by the addition of the cardiac glycoside ouabain (C-strophanthin).
KeywordsExtracellular Space Bathing Solution Endothelial Layer Extracellular Potassium Outer Capsule
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