Impairment of memory consolidation by galanin correlates with in vivo inhibition of both LTP and CREB phosphorylation.
Changes in the state of CREB phosphorylation and in LTP in the hippocampus have been associated with learning and memory. Here we show that galanin, the neuropeptide released in the hippocampal formation from cholinergic and noradrenergic fibers, that has been shown to produce impairments in memory consolidation in the Morris water maze task inhibits both LTP and CREB phosphorylation in the rat hippocampus in vivo. While there are many transmitters regulating CREB phosphorylation none has been shown to suppress behaviorally-induced hippocampal CREB phosphorylation as potently as galanin. The in vivo inhibition of dentate gyrus-LTP and of CREB phosphorylation by the agonist occupancy of GalR1 and GalR2-type galanin receptors provides strong in vivo cellular and molecular correlates to galanin-induced learning deficits and designates galanin as a major regulator of the memory consolidation process.
Kinney
Jefferson W
JW
Department of Psychology, University of Nevada, Las Vegas, NV 89154-5030, USA. Jefferson.kinney@unlv.edu
Sanchez-Alavez
Manuel
M
Barr
Alasdair M
AM
Criado
Jose R
JR
Crawley
Jacqueline N
JN
Behrens
M Margarita
MM
Henriksen
Steven J
SJ
Bartfai
Tamas
T
D000818:Animals; D015153:Blotting, Western; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D018891:Dentate Gyrus / Q000503:physiopathology; D004567:Electrodes, Implanted; D005071:Evoked Potentials; D019004:Galanin / Q000378:metabolism*; D006624:Hippocampus / Q000503:physiopathology*; D007150:Immunohistochemistry; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology; D008569:Memory Disorders / Q000503:physiopathology*; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009474:Neurons / Q000502:physiology*; D010766:Phosphorylation; D011498:Protein Precursors / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D017362:Cyclic AMP Response Element-Binding Protein; C489169:Gal protein, rat; C489787:MAP2 protein, rat; D008869:Microtubule-Associated Proteins; D011498:Protein Precursors; D019004:Galanin