THE LEVEL AND DISTRIBUTION OF THE GABABR1 AND GABABR2 RECEPTOR SUBUNITS IN THE RAT'S CENTRAL AUDITORY SYSTEM
The GABAB receptor is important for the function of neurons in the central auditory system. A functional GABAB receptor is a heterodimer of the GABABR1 and GABABR2 subunits. In this thesis, I used immunohistochemical methods to examine the level and localisation of both subunits in the rat's central auditory system. Results revealed that GABABR1 and GABABR2 subunits were expressed throughout the auditory system. High levels of immunoreactivity to both subunits were found in the superficial layers of the auditory cortex, medial geniculate nucleus, dorsal region of the inferior colliculus, and dorsal cochlear nucleus. While the expression of these subunits was generally parallel with each other, some differences were observed between the two subunits. Overall, distributions of the GABABR1 and GABABR2 subunits in auditory structures are consistent with inputs to these structures. The localisation of the subunits supports the contribution of functional GABAB receptors that are likely mediating auditory connections.