Homeostatic plasticity and the formation of neuronal assemblies in the rat hippocampus in vitro

• Applicant: Professor Dr. Uwe Heinemann (†)
• Subject Area: Molecular Biology and Physiology of Neurons and Glial Cells
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 163903388

The consolidation of hippocampus-dependent memory is likely dependent on the replay of stored information during sharp wave-ripple complexes (SPW-Rs). We have recently shown that stimuli, which induce LTP in hippocampal area CA3, also induce SPW-Rs when such stimuli are repeatedly applied, and preliminary evidence suggests that SPW-Rs induced in area CA3 can induce LTP in area CA1. During stimulus-induced SPW-Rs a subset of neurons is active while many other neurons are inhibited. We suggest that formation of neuronal assemblies, which are active during SPW-Rs, requires adaptive changes in the neuronal network including heterosynaptic plasticity to limit output, to segregate different active ensembles from each other and to prevent epileptogenesis. Employing different stimulation protocols for the induction of SPW-Rs at different sites within both hippocampal slices and slice cultures, and using different intracellular und extracellular as well as multi-unit recording techniques, in part in combination with confocal Ca2+ imaging, we will study the role of heterosynaptic plasticity on the formation and stability of neuronal assemblies.

• DFG Programme: Research Grants
• International Connection: Mexico
• Participating Persons: Professor Dr. José Bargas; Dr. Christoph J. Behrens; Professor Dr. Rafael Gutiérrez; Professor Dr. Ranulfo Romo