Involvement of brain endogenous cholecystokinin in stress-induced impairment of spatial recognition memory.
The central fragment of cholecystokinin, CCK8, plays a critical role in stress-related changes in behavior and memory. Therefore, we investigated whether the endogenous cholecystokininergic system is involved in the impairment of attention and/or memory induced by stressful conditions. Plasma corticosterone concentrations increased three-fold and plasma adrenocorticotropin (ACTH); concentrations increased five-fold when rats were maintained in the open arm of an elevated plus maze for 5 min. The same stress conditions impaired spatial recognition in the two-trial memory task. In addition, this stress led to a significant decrease in the extracellular levels of cholecystokinin-like immunoreactivity in the dorsal subiculum/CA1 of the hippocampus and partially suppressed the increase obtained during the acquisition phase of memory. This suggests that the cholecystokininergic system in the hippocampus is involved in stress-induced impairment of spatial recognition memory.
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Departement de Pharmacochimie Moléculaire et Structurale, INSERM U266, CNRS FRE2463, UFR des Sciences Pharmaceutiques et Biologiques 4 avenue de l'Observtoire, 75270 06, Paris cedex, France. dauge@im3.inserm.fr
Pophillat
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Crété
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Melik-Parsadaniantz
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Roques
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D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology; D002766:Cholecystokinin / Q000172:deficiency*; D003345:Corticosterone / Q000097:blood; D015536:Down-Regulation / Q000502:physiology; D006624:Hippocampus / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008569:Memory Disorders / Q000378:metabolism* / Q000503:physiopathology; D009434:Neural Pathways / Q000378:metabolism* / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000378:metabolism* / Q000503:physiopathology
D000324:Adrenocorticotropic Hormone; D002766:Cholecystokinin; D003345:Corticosterone