| Description |
Neuronal nicotinic acetylcholine receptors (nAChRs) belong to a family of; ligand-gated transmitter receptors that includes muscle nicotinic receptors, GABA; receptors and glycine receptors. As the structures of neuronal nAChRs are elucidated,; inquiries arise about the functional properties of these receptors. The physiological; importance of neuronal nAChRs may be understood by determining the location of the; individual subunits in the murine brain. Through immunostaining, this study finds that; the B4 subunits of nAChRs are located primarily in auditory pathways, in the medial; habenular/interpeduncular nucleus protein transport pathway, in the trigeminal pathway,; in the piriform cortex/olfactory bulb pathway and in other selected nuclei throughout the; murine brain. These results suggest that the B4 subunit could be physiologically; important in neuronal transmission and regulation in the aforementioned pathways.; Aging may be one neuronal process in which nAChRs are involved. In this study; we compared immunostaining of different receptor subunits (a4, as, a7, B4) in the; hippocampus of both young and aged animals. Notable decreases in immunostaining of; a4, as and a7 were seen in various areas ofthe aged mice, including: the CAl; pyramidal layer, the CAl stratum oriens layer and the CA2/3 region. However, nAChR; B4 showed no decrease in aged animals in the CAl pyramidal cell layer. Other; age-specific differences showed independent staining patterns between subunit types.; These results provide evidence that neuronal aging may be correlated with expression of; certain nAChR subunits. |
