Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

The role of Ca2+ in the generation of spontaneous astrocytic Ca2+ oscillations

Parri, H. R. and Crunelli, Vincenzo 2003. The role of Ca2+ in the generation of spontaneous astrocytic Ca2+ oscillations. Neuroscience 120 (4) , pp. 979-992. 10.1016/S0306-4522(03)00379-8

Full text not available from this repository.

Abstract

Astrocytes in the rat thalamus display spontaneous [Ca2+]i oscillations that are due to intracellular release, but are not dependent on neuronal activity. In this study we have investigated the mechanisms involved in these spontaneous [Ca2+]i oscillations using slices loaded with Fluo-4 AM (5 μM) and confocal microscopy. Bafilomycin A1 incubation had no effect on the number of spontaneous [Ca2+]ioscillations indicating that they were not dependent on vesicular neurotransmitter release. Oscillations were also unaffected by ryanodine. Phospholipase C (PLC) inhibition decreased the number of astrocytes responding to metabotropic glutamate receptor (mGluR) activation but did not reduce the number of spontaneously active astrocytes, indicating that [Ca2+]iincreases are not due to membrane-coupled PLC activation. Spontaneous [Ca2+]iincreases were abolished by an IP3 receptor antagonist, whilst the protein kinase C (PKC) inhibitor chelerythrine chloride prolonged their duration, indicating a role for PKC and inositol 1,4,5,-triphosphate receptor activation. BayK8644 increased the number of astrocytes exhibiting [Ca2+]i oscillations, and prolonged the responses to mGluR activation, indicating a possible effect on store-operated Ca2+ entry. Increasing [Ca2+]oincreased the number of spontaneously active astrocytes and the number of transients exhibited by each astrocyte. Inhibition of the endoplasmic reticulum Ca2+ ATPase by cyclopiazonic acid also induced [Ca2+]itransients in astrocytes indicating a role for cytoplasmic Ca2+in the induction of spontaneous oscillations. Incubation with 20 μM Fluo-4 reduced the number of astrocytes exhibiting spontaneous increases. This study indicates that Ca2+ has a role in triggering Ca2+release from an inositol 1,4,5,-triphosphate sensitive store in astrocytes during the generation of spontaneous [Ca2+]i oscillations.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Biosciences
Neuroscience and Mental Health Research Institute (NMHRI)
ISSN: 0306-4522
Last Modified: 04 Jun 2017 06:30
URI: http://orca-mwe.cf.ac.uk/id/eprint/61090

Citation Data

Cited 94 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item