Article
Sodium-Calcium Exchanger Modulates the L-Glutamate Ca i 2+ Signalling in Type-1 Cerebellar Astrocytes
Registro en:
Avances en Medicina Experimental y Biología 961
DOI 10.1007/978-1-4614-4756-6_22,
Autor
Rojas, H
Colina, C
Ramos, M
Benaím, Gustavo
Jaffe, E
Caputo, C
Di Polo, R
Institución
Resumen
We have previously demonstrated that rat type-1 cerebellar astrocytes
express a very active Na + /Ca 2+ exchanger which accounts for most of the
total plasma membrane Ca 2+ fl uxes and for the clearance of Ca i 2+ induced
by physiological agonist. In this chapter, we have explored the mechanism
by which the reverse Na + /Ca 2+ exchange is involved in agonistinduced
Ca 2+ signalling in rat cerebellar astrocytes. Laser-scanning
confocal microscopy experiments using immuno fl uorescence labelling of
Na + /Ca 2+ exchanger and RyRs demonstrated that they are highly co-localized.
The most important fi nding presented in this chapter is that
L -glutamate activates the reverse mode of the Na + /Ca 2+ exchange by
inducing a Na + entry through the electrogenic Na + -glutamate co-transporter
and not through the ionophoric L -glutamate receptors as con fi rmed
by pharmacological experiments with speci fi c blockers of ionophoric
L -glutamate receptors, electrogenic glutamate transporters and the Na/Ca
exchange.