Premium
Effects of Ca ions on action potentials in immature cultured neurons from chick cerebral cortex
Author(s) -
Mori Junko,
Ashida Hiroshi,
Maru Eiichi,
Tatsuno Jiro
Publication year - 1982
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041100303
Subject(s) - tetrodotoxin , depolarization , cerebral cortex , cortex (anatomy) , biophysics , cortical neurons , chemistry , biology , neuroscience
Action potentials evoked by depolarizing pulses were studied in immature cultured cerebral cortical neurons from chick embryos. The majority of action potentials were rather small, and they were still elicited in the presence of 10 −7 gm/ml tetrodotoxin (TTX), but were almost completely abolished in Na + ‐free solution or by 10 −5 gm/ml TTX in Tyrode's solution. The elevation of external Ca 2+ concentration not only increased the maximum rates of rise of action potentials in normal Tyrode's solution with and without low (10 −7 gm/ml) TTX but also regenerated action potentials in high (10 −5 gm/ml) TTX‐containing Tyrode's solution or in Na + ‐free solution. These high Ca 2+ effects were blocked by Mn 2+ or Co 2+ . These results suggest that action potentials, which were predominantly Na‐dependent, are partially contributed by Ca ions in immature chick cerebral cortical neurons.