Independent cellular and ontogenetic expression of mRNAS encoding three α polypeptides of the rat GABAA receptor

Five subtypes of type A gamma-aminobutyric acid receptors identified in neurons by double and triple immunofluorescence staining with subunit-specific antibodies.

“…The existence of further subtypes of GABAA receptors containing subunits not analyzed here is likely, as indicated by the presence of both a6 and 8 subunits in cerebellar granule cells (7,22,23) and the high expression of a2-subunit mRNA in brainstem motoneurons (9).…”

“…The subunit specificity of the corresponding antisera is evidenced by (i) the selective recognition of subunits in purified GABAA receptors by Western blotting (13)(14)(15); (ii) the correlation between the regional distribution of the subunit IR and the respective mRNA visualized by in situ hybridization (8)(9)(10)(11)21), except for the a3 subunit in cerebellum (12,28); (iii) the correlation between the absence of subunit IR and lack of subunit mRNA signal, most clearly seen for the al subunit in striatum and olfactory bulb granule cells (9) (Table 1). An association of these subunits in receptor complexes is made likely by several lines of evidence.…”

“…Since antibodies for single P subunits are not available, the monoclonal antibody bd-17 (16,17), which recognizes both the P2 and the f3 subunit (18), was used to represent the /-subunit family. Subunits not included in the present study are not of major preponderance (a2, a4, a5, 81, yi, )y3, p) (5,8,9,11,(19)(20)(21) or are largely restricted to a particular population of neuronse.g., cerebellar granule cells (a6, 8) (7,22,23). The present analysis was restricted to the olfactory bulb, basal forebrain, basal ganglia, brainstem, and cerebellum, where the pattern of subunit distribution was most distinctive.…”

“…So far, the distribution of subunits has largely been mapped at the mRNA level (6)(7)(8)(9)(10)(11)(12). However, the coassembly of subunits and the presence of multiple receptors in a single neuron can be demonstrated only by detailed immunohistochemical analysis.…”

Plasticity in GABAAReceptor Subunit mRNA Expression by Hypothalamic Magnocellular Neurons in the Adult Rat

“…To date, such studies have concentrated on developmental regulation, including changes during aging (MacLennan et al, 1991;Poulter et al, 1993;Fritschy et al, 1994;Gutierrez et al, 1994;Mathews et al, 1994), and examined the response of GABA A receptor expression and function in adults to a variety of allosteric GABA A receptor modulators (Kang and Miller, 1991;Montpied et al, 1991;Primus and Gallager, 1992;Mhatre et al, 1993;Tseng et al, 1994) as well as excitatory and inhibitory amino acids (Kim et al, 1993;Mhatre and Ticku, 1994;Zhu et al, 1995;Fénelon and Herbison, 1996). Further work has examined GABA A receptor expression in pathological states such as epilepsy (Kokaia et al, 1994;Kamphuis et al, 1995), Huntington's disease (Faull et al, 1993), and chronic stress (Montpied et al, 1993).…”