RT Journal Article SR Electronic T1 Functional Correlation of GABAA Receptor α Subunits Expression with the Properties of IPSCs in the Developing Thalamus JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 2202 OP 2208 DO 10.1523/JNEUROSCI.20-06-02202.2000 VO 20 IS 6 A1 Masayoshi Okada A1 Kayoko Onodera A1 Catherine Van Renterghem A1 Werner Sieghart A1 Tomoyuki Takahashi YR 2000 UL http://www.jneurosci.org/content/20/6/2202.abstract AB GABAA receptor α1 and α2 subunits are expressed differentially with ontogenic period in the brain, but their functional roles are not known. We have recorded GABAAreceptor-mediated IPSCs from laterodorsal (LD) thalamic relay neurons in slices of rat brain at various postnatal ages and found that decay times of evoked IPSCs and spontaneous miniature IPSCs undergo progressive shortening during the first postnatal month. With a similar time course, expression of transcripts and proteins of GABAA receptor α2 subunit in LD thalamic region declined, being replaced by those of α1 subunit. To further address the causal relationship between α subunits and IPSC decay time kinetics, we have overexpressed GABAA receptor α1 subunit together with green fluorescent protein in LD thalamic neurons in organotypic culture using recombinant Sindbis virus vectors. Miniature IPSCs recorded from the LD thalamic neurons overexpressed with α1 subunit had significantly faster decay time compared with control expressed with β-galactosidase. We conclude that the α2-to-α1 subunit switch underlies the developmental speeding in the decay time of GABAergic IPSCs.