Recent studies41 suggest that variations in maternal care might actually permanently alter the composition of the GABAA receptor complex in the offspring. The G ABAA receptor is comprised of five individual protein subunits that collectively form a functional CI- channel mediating GABA-induced neuronal inhibition in the adult brain. There are over 20 individual subunits and variation in the function of the GABAA receptor is associated with differences in the nature of the subunits comprising the receptor. Of particular interest are the a and y subunits, the presence of which defines a BZ binding site. The offspring of the high-LG mothers show increased levels of the mRNAs for the γ1 and γ2 subunits, both of which contribute to the formation of a functional BZ binding site. Such differences are not unique to the γ subunits. Levels of mRNA for the α subunit of the GABAAA/BZ receptor complex are significantly higher in the amygdala and locus ceruleus of high-LG compared with low-LG offspring. The α1 subunit appears to confer higher affinity for GABA, providing the most efficient form of the GABAA receptor
