Premium
Glutamate‐induced increase in intracellular Ca 2+ concentration in isolated hippocampal neurones
Author(s) -
Kudo Yoshihisa,
Ogura Akihiko
Publication year - 1986
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1986.tb11135.x
Subject(s) - glutamate receptor , kainate receptor , biophysics , fura 2 , extracellular , nmda receptor , intracellular , hippocampal formation , calcium , chemistry , medicine , biology , endocrinology , biochemistry , receptor , ampa receptor , cytosol , enzyme
1 A system for real‐time quantitative monitoring of intracellular free calcium ion concentration ([Ca 2+ ] i ) on a single cell basis was developed by the combination of a fluorescent Ca 2+ indicator fura‐2, a fluorescence microscope, a video‐camera and photometrical devices. It was applied to rat individual hippocampal neurones under culture for detection of L‐glutamate‐induced alterations in the [Ca 2+ ] i level. 2 L‐Glutamate (0.01–100 μM) induced a dose‐dependent elevation of the [Ca 2+ ] i . The [Ca 2+ ] i in the rat hippocampal neurone was found to be around 30 nM in the resting state, and was increased up to 500 nM by the application of 100 μM L‐glutamate. N ‐methyl‐D‐aspartate, kainate and quisqualate in a concentration of 10 μM also increased the [Ca 2+ ] i level in the same single neurone, but their efficacy varied between individual cells. 3 The L‐glutamate‐induced [Ca 2+ ] i elevation was abolished after removal of extracellular Ca 2+ and was much reduced by Mg 2+ (3 mM). The increase was, however, still observed in a Na + ‐free medium. 4 The L‐glutamate‐induced [Ca 2+ ] i elevation was not affected substantially after treatment with nitrendipine (10 μM) which blocked the increase in [Ca 2+ ] i induced by an isotonic high KCl‐medium (50 mM). 5 The present results suggest that the L‐glutamate‐induced [Ca 2+ ]i elevation in the hippocampal neurone is due to an influx of Ca 2+ through both L‐glutamate receptor‐coupled and voltage‐sensitive ionic channels.