Three ¦Â Subunit Of The Gabaa Receptor Mrna (¦Â1, ¦Â2 And ¦Â3) Changes In The Distribution Of Rat Brain After Birth

PART I The Region-specific Expression of the mRNAs Encoding β Subunits (β 1,β 2,and β 3) of GABA_A Receptor in the Rat BrainThe expression of mRNAs encoding different β subunits (β 1, β 2 and β3) of the gamma-aminobutyric acid_A (GABA_A) receptor in the rat brain was investigated by in situ hybridization histochemistry. Transcripts of each subunit showed region-specific localization. Some areas contained all three β subunit mRNAs, while other areas showed marked differences in the location and level of expression of each subunit mRNA. The regions with strong to very strong labeling by the β 3 probe were as follows: the olfactory bulb, the cortex, the caudate-putamen, the accumbens nucleus, the hypothalamus, the amygdala, the hippocampal formation, and some areas of the brainstem and spinal cord. Weak to moderate labeling was detected in the thalamus, superior and inferior colliculus, and many areas of the brainstem. The regions with strong to very strong labeling by the β 2 probe were as follows: the olfactory bulb, the ventral pallidum, the globus pallidus, the nucleus of the diagonal band, the preoptic magnocellular nucleus, the thalamus, the subthalamic nucleus, the substantia nigra, and the cerebellum. Weak to moderate labeling was detected in the regions that showed strong expression of β 3 subunit mRNA. Expression of β 1 subunit mRNA was only weak to moderate compared to that of the β 2 and...