Effects of extracellular potassium concentration and postsynaptic membrane potential on calcium-induced potentiation in area CA1 of rat hippocampus.
Title
Effects of extracellular potassium concentration and postsynaptic membrane potential on calcium-induced potentiation in area CA1 of rat hippocampus.
Creator
Grover L M; Teyler T J
Publisher
Brain research
Date
1990
1990-01
Description
Long-lasting potentiation can be induced in area CA1 of hippocampus by a relatively brief (7-10 min) exposure to a higher (4.0 mM) than normal (2.0 mM) extracellular calcium concentration. We have found that long-lasting calcium-induced potentiation is dependent on extracellular potassium concentration. Slices exposed to high extracellular calcium in the presence of normal extracellular potassium (3.35 mM) showed a transient facilitation. Long-lasting potentiation was induced by exposure to high calcium only in slices also exposed to higher than normal extracellular potassium (6.25 mM). In intracellular experiments we found that injection of depolarizing current into postsynaptic neurons could substitute for high extracellular potassium. These results suggest that calcium-induced potentiation involves a postsynaptic, voltage-dependent mechanism. A similar conclusion has been reached for tetanus-induced potentiation. We also found that calcium-induced potentiation, like tetanus-induced potentiation, is not accompanied by an increase in postsynaptic input resistance.
Subject
Animals; Rats; Action Potentials/drug effects; Membrane Potentials/drug effects; Potassium/*pharmacology; Hippocampus/drug effects/*physiology; Neuronal Plasticity/*drug effects; Calcium/*pharmacology
Identifier
Rights
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
Citation
Grover L M; Teyler T J, “Effects of extracellular potassium concentration and postsynaptic membrane potential on calcium-induced potentiation in area CA1 of rat hippocampus.,” NEOMED Bibliography Database, accessed April 18, 2024, https://neomed.omeka.net/items/show/5450.