Distinct patterns of expression and regulation of GABA receptors containing the delta subunit in cerebellar granule and hippocampal neurons

FOLLESA, PAOLO;MOSTALLINO MC;BIGGIO, FRANCESCA;GORINI G;CARIA S;BUSONERO, FABIO;MURRU, LUCA;MURA ML;SANNA, ENRICO;BIGGIO G.

2005-01-01

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Abstract

Neuronal plasticity is achieved by regulation of the expression of genes for neurotransmitter receptors such as the type A receptor (GABAAR) for γ-aminobutyric acid. We now show that two different rat neuronal populations in culture manifest distinct patterns of GABAAR plasticity in response to identical stimuli. Whereas prolonged exposure to ethanol had no effect on expression of the δ subunit of GABAARs at the mRNA or protein level in cerebellar granule neurons, it increased the abundance of δ subunit mRNA and protein in hippocampal neurons. Subsequent ethanol withdrawal transiently down-regulated δ subunit expression in cerebellar granule neurons and gradually normalized that in hippocampal neurons. These effects of ethanol exposure and withdrawal were accompanied by corresponding functional changes in GABAARs. GABAARs containing the δ subunit were also distributed differentially in the cerebellar and hippocampal neurons. These findings reveal complex and distinct mechanisms of regulation of the expression of GABAARs that contain the δ subunit in different neuronal types. © 2005 International Society for Neurochemistry.