Changes in spatial memory following intra-CA3 injections of kainate in rats

Kainate receptors (KARs) are involved in short- and long-term plasticity at mossy fibreCA3 synapses in vitro. Since the majority of research conducted to date has been restricted to in vitro experiments, the objective of the present thesis was to activate KARs with low doses of kainate and determine how this manipulation influenced synaptic plasticity in vivo. It was hypothesized that spatial information processing improvements would be observed at doses showing potentiated responses in vitro. Post-training intra-CA3 injections of 100 nM kainate led to the greatest enhancement in spatial memory performance, demonstrating a potential role for KARs in the consolidation of spatial information. These findings imply that the administration of kainate into the CA3 may lead to enhanced expression of spatial information in vivo and parallel in vitro findings that kainate receptors play a critical role in multiple forms of plasticity at the mossy fiber synapse.