Differences in glutamate-mediated calcium responses in the ventral cochlear nucleus and inferior colliculus of the developing rat

Both mGluR1 and mGluR5 subtypes of group I mGluRs were present in the CIC and the VCN. However, Group I mGluR [Ca2+]i responses elicited by DHPG were two fold higher in CIC than in VCN neurons. Therefore, our findings suggest that Ca2+ signalling in auditory neurons may be differentially regulated at different levels of the auditory pathway through preferential activation of different classes of glutamate receptors, which may have implications for hierarchical auditory signal processing and plasticity, at least during the early developmental stages of hearing.