Dr Brian Billups, Eccles Institute of Neuroscience, The John Curtin School of Medical Research, ANU, Canberra, ACT.
Neurons in the brain release large quantities of neurotransmitters, which stimulate receptors on their neighbours to signal neural activity. Following activation, this signal must be rapidly terminated to allow fast repetition of communication, which is commonly achieved by sequestering the neurotransmitter back into cells via active transport processes. The action of the most abundant neurotransmitter, glutamate, is terminated by sequestration into neighbouring glial cells by high-affinity glutamate transporters. The transfer of glutamate from neurons to glia ultimately depletes neurons of this vital resource, which would inhibit neurotransmission. The focus of my seminar concerns the mechanisms that neurons use to recycle or otherwise replenish glutamate in the central nervous system. I will highlight the role that glial cells play is synthesising glutamine and how this can be transferred back to neurons to regenerate glutamate. As efficient glutamate recycling is essential to sustain continuous neurotransmission, identification of the biochemical pathways involved in this process will have important implications for the treatment of multiple CNS disorders.