This is an historical archive of the activities of the MRC Anatomical Neuropharmacology Unit (MRC ANU) that operated at the University of Oxford from 1985 until March 2015. The MRC ANU established a reputation for world-leading research on the brain, for training new generations of scientists, and for engaging the general public in neuroscience. The successes of the MRC ANU are now built upon at the MRC Brain Network Dynamics Unit at the University of Oxford.

Hippocampal interneurons support behaviour

Damien Lapray and his collaborators at Oxford and Vienna explored how the firing rate and patterns of GABAergic interneurons is adjusted in the neuronal network to ongoing behaviour in freely moving rats. They used novel innovative technology to record and label single GABAergic neurons while the rat moved, slept or just kept quiet in a small arena. Recorded parvalbumin–expressing basket interneurons innervate somata and proximal pyramidal cell dendrites, whereas nitric–oxide–synthase– and neuropeptide–Y–expressing ivy cells provide synaptic and extrasynaptic dendritic modulation. Basket and ivy cells showed distinct spike timing dynamics, firing at different rates and times during theta and ripple oscillations. Basket but not ivy cells changed their firing rates during movement, sleep and quiet wakefulness, suggesting that basket cells coordinate cell assemblies in a behavioral state–contingent manner, whereas persistently–firing ivy cells might control network excitability and homeostasis. Different interneuron types provide GABA to specific subcellular domains at defined times and rates, thus differentially controlling network activity during behavior.