Effects of orexin-A on memory processing.
Orexin-A is an endogenous peptide with receptors present throughout the brain. Here, we examined the effect of post-training administration of orexin-A on retention in active and passive avoidance. Orexin-A administered by intracerebroventricular (i.c.v.) injection to CD-1 mice post-training improved retention in both T-maze footshock avoidance and one trial step-down passive avoidance. SAMP8 mice have age-related deficits in learning and memory, which correlate with an increase in brain levels of beta amyloid (Abeta) and an impaired response to memory-enhancing compounds. Orexin-A at 3nmol improved retention in young and old SAMP8 mice. These findings show that orexin-A can improve memory even with overproduction of Abeta.
Jaeger
Laura B
LB
Geriatric Research Education and Clinical Center (GRECC), VA Medical Center, St. Louis, MO 63106, USA.
Farr
Susan A
SA
Banks
William A
WA
Morley
John E
JE
D016229:Amyloid beta-Peptides / Q000096:biosynthesis; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001921:Brain / Q000187:drug effects*; D002352:Carrier Proteins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects*; D051379:Mice; D009479:Neuropeptides / Q000494:pharmacology*; D000068797:Orexins; D013997:Time Factors
D016229:Amyloid beta-Peptides; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins