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Fig. 8. Two phases of the [Ca2+]c rise by activation of the
metabotropic glutamate receptors. (A) Application of 10 µM DHPG (a)
elicited characteristic [Ca2+]c rises: the initial
transient Ca2+ rise and long-sustained
[Ca2+]c elevation (n=7). Disappearance of the
later persistent [Ca2+]c elevation (b) under the
Ca2+-free solution (n=7). (B) Effects of glutamate
receptor antagonists on the late phase of glutamate-induced
[Ca2+]c increases. All the solutions contain 1 µM
glycine. Note the glutamate concentration.