In vitro measurements of extracellular L-glutamate level in region CA3 of mouse hippocampal slices under chemical stimulation.
The concentration level of extracellular L-glutamate released from region CA3 of mouse hippocampal slices under tetraethylammonium (TEA) chloride and KCl stimulation was measured with independent methods, i.e., a capillary-based enzyme sensor, a patch sensor, and an enzyme-based imaging method. The L-glutamate level was compared with those at regions CA1 and DG. It was found that the enhanced concentration level at CA3 by TEA stimulation is very similar to that at CA1, but it is much lower than that at DG. The order of the regional distribution of L-glutamate, i.e., DG > CA1 ≈ CA3, was the same as that obtained by K(+) stimulation. However, in the presence of an uptake inhibitor, DL-TBOA, KCl stimulation showed the strongest L-glutamate flux at CA1, while TEA stimulation exhibited the strongest flux at CA3. The usefulness of the present approach for knowing the extracellular L-glutamate level in acute hippocampal slices is discussed.
Department of Chemistry, College of Humanities and Sciences, Nihon University, Sakurajuosui, Setagaya, Tokyo 156-8550, Japan.
Hiromi
H
Chiba
Yukari
Y
Deguchi
Ena
E
Kanazawa
Jun
J
Kawai
Keiichiro
K
Nozawa
Atsushi
A
Shoji
Masao
M
Sugawara
D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D056654:CA3 Region, Hippocampal / Q000737:chemistry* / Q000378:metabolism; D018698:Glutamic Acid / Q000032:analysis* / Q000378:metabolism; D051379:Mice; D011189:Potassium Chloride / Q000494:pharmacology; D013268:Stimulation, Chemical; D019789:Tetraethylammonium / Q000494:pharmacology
C120673:benzyloxyaspartate; D001224:Aspartic Acid; D018698:Glutamic Acid; D019789:Tetraethylammonium; D011189:Potassium Chloride