Depolarization with high-K+ causes Ca(2+)-independent but partially Cl(-)-dependent glutamate release in rat hippocampal slice cultures.
We studied the neurotoxic glutamate release induced by high-K+ depolarization in rat hippocampal slice cultures. Depolarization with 90 mM K+ for 30 min caused a significant, three-fold increase in glutamate release. This release was not inhibited by removing extracellular Ca2+, but was significantly inhibited by replacement of extracellular Cl- with SO4(2-). These findings suggest that glutamate is released by mechanisms other than conventional vesicular release under the high-K+ condition.
Takahashi
M
M
Tsukuba Research Laboratories, Upjohn Pharmaceuticals Limited, Ibaraki, Japan.
Hashimoto
M
M
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology*; D046508:Culture Techniques; D018698:Glutamic Acid / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology*; D051381:Rats
D002712:Chlorides; D018698:Glutamic Acid; D011188:Potassium; D002118:Calcium