RT Journal Article
SR Electronic
T1 Two Functionally Distinct Serotonergic Projections into Hippocampus
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 4936
OP 4944
DO 10.1523/JNEUROSCI.2724-19.2020
VO 40
IS 25
A1 Luchetti, Alessandro
A1 Bota, Ayaka
A1 Weitemier, Adam
A1 Mizuta, Kotaro
A1 Sato, Masaaki
A1 Islam, Tanvir
A1 McHugh, Thomas J.
A1 Tashiro, Ayumu
A1 Hayashi, Yasunori
YR 2020
UL http://www.jneurosci.org/content/40/25/4936.abstract
AB Hippocampus receives dense serotonergic input specifically from raphe nuclei. However, what information is carried by this input and its impact on behavior has not been fully elucidated. Here we used in vivo two-photon imaging of activity of hippocampal median raphe projection fibers in behaving male and female mice and identified two distinct populations: one linked to reward delivery and the other to locomotion. Local optogenetic manipulation of these fibers confirmed a functional role for these projections in the modulation of reward-induced behavior. The diverse function of serotonergic inputs suggests a key role in integrating locomotion and reward information into the hippocampal CA1.SIGNIFICANCE STATEMENT Information constantly flows in the hippocampus, but only some of it is captured as a memory. One potential process that discriminates which information should be remembered is concomitance with reward. In this work, we report a neuromodulatory pathway, which delivers reward signal as well as locomotion signal to the hippocampal CA1. We found that the serotonergic system delivers heterogeneous input that may be integrated by the hippocampus to support its mnemonic functions. It is dynamically involved in regulating behavior through interaction with the hippocampus. Our results suggest that the serotonergic system interacts with the hippocampus in a dynamic and behaviorally specific manner to regulate reward-related information processing.