title: Change in calcium permeability caused by quinolinic acid in cultured rat hippocampal neurons.
abstract: The calcium permeability of receptor channels activated by quinolinic acid (QUIN) in cultured rat hippocampal neurons was investigated using the whole-cell voltage-clamp method. In Na+-free, 10 mM Ca2+ solution with the internal solution containing 165 mM Cs+, QUIN elicited prominent inward currents at -60 mV, and the reversal potential of the QUIN-induced current was -5.8 +/- 1.2 mV, indicating that QUIN-activated channels are highly permeable to Ca2+ (permeability ratio PCa2+/PCs+ = 5.9). This result was substantiated by microfluorometry using fura-2, which revealed that QUIN caused a marked increase in the intracellular Ca2+ concentration even after the voltage-dependent Ca2+ channels had been suppressed by La3+.
authors.affiliation: Department of Physiology, School of Medicine, Gunma University, Maebashi, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tsuzuki
authors.forename: M
authors.initials: M
authors.lastname: Iino
authors.forename: S
authors.initials: S
authors.lastname: Ozawa
mesh_terms: D000818:Animals; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D005260:Female; D005470:Fluorometry; D016257:Fura-2; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D010539:Permeability; D011188:Potassium / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology*; D011805:Quinolinic Acids / Q000494:pharmacology*; D051381:Rats
chemical_list: D001572:Benzofurans; D011725:Pyridines; D011805:Quinolinic Acids; D011188:Potassium; D002118:Calcium; D016257:Fura-2