Distribution of the GABAA receptor ?1- and ?2-subunit mRNAs in chick brain

Abstract

We have used sequence-specific oligonucleotide probes and in situ hybridisation histochemistry to examine the distributions of the GABAA receptor ?1- and ?2-subunit mRNAs in serial sections of 1-day-old chick brain. Both transcripts are present together, at high levels, in many brain regions. Differences are found, however, in the relative amounts of these mRNAs in two isthmic nuclei of the optic lobe, the deep cerebellar nuclei, and the dorsal thalamus. We therefore conclude that while the ?1 and ?2 subunits predominantly occur together in the same receptor complex, they may also be found separately in other GABAA receptor subtypes