Locus coeruleus and dopaminergic consolidation of everyday memory.
The retention of episodic-like memory is enhanced, in humans and animals, when something novel happens shortly before or after encoding. Using an everyday memory task in mice, we sought the neurons mediating this dopamine-dependent novelty effect, previously thought to originate exclusively from the tyrosine-hydroxylase-expressing (TH+) neurons in the ventral tegmental area. Here we report that neuronal firing in the locus coeruleus is especially sensitive to environmental novelty, locus coeruleus TH+neurons project more profusely than ventral tegmental area TH+neurons to the hippocampus, optogenetic activation of locus coeruleus TH+neurons mimics the novelty effect, and this novelty-associated memory enhancement is unaffected by ventral tegmental area inactivation. Surprisingly, two effects of locus coeruleus TH+photoactivation are sensitive to hippocampal D1/D5receptor blockade and resistant to adrenoceptor blockade: memory enhancement and long-lasting potentiation of synaptic transmission in CA1 ex vivo. Thus, locus coeruleus TH+neurons can mediate post-encoding memory enhancement in a manner consistent with possible co-release of dopamine in the hippocampus.
Centre for Cognitive and Neural Systems, Edinburgh Neuroscience, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, UK.
Tomonori
T
Takeuchi
Centre for Cognitive and Neural Systems, Edinburgh Neuroscience, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, UK.
Adrian J
AJ
Duszkiewicz
University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
Alex
A
Sonneborn
Centre for Cognitive and Neural Systems, Edinburgh Neuroscience, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, UK.
Patrick A
PA
Spooner
Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, 060-8638, Japan.
Miwako
M
Yamasaki
Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, 060-8638, Japan.
Masahiko
M
Watanabe
University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.
Caroline C
CC
Smith
Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Nijmegen, 6525 EZ, The Netherlands.
Guillén
G
Fernández
Departments of Psychiatry and Behavioral Sciences and of Bioengineering, Stanford University, Stanford, California 94305, USA.
Karl
K
Deisseroth
University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA.|International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, 305-8575, Japan.
Robert W
RW
Greene
Centre for Cognitive and Neural Systems, Edinburgh Neuroscience, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, UK.|Instituto de Neurociencias, CSIC-UMH, Alicante, 03550, Spain.
Richard G M
RG
Morris
D000818:Animals; D056547:CA1 Region, Hippocampal / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D004298:Dopamine / Q000378:metabolism*; D066298:In Vitro Techniques; D008125:Locus Coeruleus / Q000166:cytology / Q000502:physiology* / Q000528:radiation effects; D008297:Male; D000069077:Memory Consolidation / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000378:metabolism / Q000528:radiation effects; D062308:Optogenetics; D011941:Receptors, Adrenergic / Q000378:metabolism; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D050641:Receptors, Dopamine D5 / Q000037:antagonists & inhibitors / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects; D017557:Ventral Tegmental Area / Q000166:cytology / Q000502:physiology
D011941:Receptors, Adrenergic; D017447:Receptors, Dopamine D1; D050641:Receptors, Dopamine D5; D004298:Dopamine