The Effect of Glutamate Receptor Agonists on Mouse Retinal Astrocyte [Ca2+]i

Abstract

Calcium-imaging techniques were used to determine if mouse retinal astrocytesin siturespond to agonists of ionotropic (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, AMPA; N-methyl-D-aspartate, NMDA) and metabotropic (S-3,5-dihydroxyphenylglycine, DHPG;trans-1-amino-1,3-cyclopentanedicarboxylic acid, ACPD) glutamate receptors. In most cases we found no evidence that retinal astrocyte intracellular calcium ion concentration (Ca2+i) increased in response to these glutamate agonists. The one exception was AMPA that increasedCa2+iin some, but not all, mouse retinal astrocytesin situ. However, AMPA did not increaseCa2+iin mouse retinal astrocytesin vitro, suggesting that the effect of AMPAin situmay be indirect.