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bioRxiv · 10.1101/712596

In vivo characterization of neurophysiological diversity in the lateral supramammillary nucleus during hippocampal sharp-wave ripples of adult rats

Vicente, A. F.·Slezia, A.·Ghestem, A.·Bernard, C.·Quilichini, P. P.
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Abstract

The extent of the networks that control the genesis and modulation of hippocampal sharp wave ripples (SPW-Rs), which are involved in memory consolidation, remains incompletely understood. Here, we performed a detailed in vivo analysis of single cell firing in the lateral supramammillary nucleus (lSuM) during theta and slow oscillations, including SPW-Rs, in anesthetized rats. We classified neurons as SPW-R-active and SPW-R unchanged according to whether or not they increased their firing during SPW-Rs. We show that lSuM SPW-R-active neurons increase their firing prior SPW-Rs peak power and prior hippocampal pyramidal cell activation. Moreover, lSuM SPW-R-active neurons show increased firing activity during theta and slow oscillations as compared to unchanged-neurons. SPW-R-active neurons are more active during high peak power SPW-Rs, whereas SPW-R-unchanged neurons are more active during long SPW-Rs. These results suggest that a sub-population of lSuM neurons can interact with the hippocampus during SPW-Rs, raising the possibility that the lSuM may modulate memory consolidation.

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Vicente, A. F., Slezia, A., Ghestem, A., Bernard, C., Quilichini, P. P.. 2019-07-24. In vivo characterization of neurophysiological diversity in the lateral supramammillary nucleus during hippocampal sharp-wave ripples of adult rats. https://doi.org/10.1101/712596

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