Journal article

Modulation of hippocampal theta oscillations and spatial memory by relaxin-3 neurons of the nucleus incertus

Sherie Ma, Francisco E Olucha-Bordonau, M Akhter Hossain, Feng Lin, Chester Kuei, Changlu Liu, John D Wade, Steven W Sutton, Angel Nunez, Andrew L Gundlach



Hippocampal theta rhythm is thought to underlie learning and memory, and it is well established that "pacemaker" neurons in medial septum (MS) modulate theta activity. Recent studies in the rat demonstrated that brainstem-generated theta rhythm occurs through a multisynaptic pathway via the nucleus incertus (NI), which is the primary source of the neuropeptide relaxin-3 (RLN3). Therefore, this study examined the possible contribution of RLN3 to MS activity, and associated hippocampal theta activity and spatial memory. In anesthetized and conscious rats, we identified the ability of intraseptal RLN3 signaling to modulate neuronal activity in the MS and hippocampus and promote hippocampal thet..

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Awarded by National Health and Medical Research Council (NHMRC) of Australia

Awarded by ISCIII-FIS of the Ministry of Health

Funding Acknowledgements

This research was supported by grants from the National Health and Medical Research Council (NHMRC) of Australia (# 520299 to S. M., # 277609 and # 509246 to A. L. G., and # 509048 to J.D.W.), from the ISCIII-FIS of the Ministry of Health (PI061816 FEOB), and a collaborative research agreement between the Howard Florey Institute and Johnson & Johnson Pharmaceutical Research & Development, LLC. S. M. is a recipient of an NHMRC Australian Biomedical Fellowship, and J.D.W. and A. L. G. are NHMRC (Australia) Research Fellows. We thank Maria Teresa Minguez (SCSIE-UV) for her technical assistance in preparing EM samples. We also thank the Howard Florey Biomedical Foundation (USA), Ian Potter Foundation of Australia, ANZ Trustees Medical Research and Technology, and the GW Vowell Foundation for their support.