Memory retrieval impairment induced by hippocampal CA3 lesions is blocked by adrenocortical suppression.
There is evidence that in rats, partial hippocampal lesions or selective ablation of the CA3 subfield can disrupt retrieval of spatial memory and that hippocampal damage disinhibits hypothalamic-pituitary-adrenocortical (HPA)-axis activity, thereby elevating plasma levels of adrenocorticotropin and corticosterone. Here we report evidence that attenuation of CA3 lesion-induced increases in circulating corticosterone levels with the synthesis inhibitor metyrapone, administered shortly before water-maze retention testing, blocks the impairing effects of the lesion on memory retrieval. These findings suggest that elevated adrenocortical activity is critical in mediating memory retrieval deficits induced by hippocampal damage.
Roozendaal
B
B
Center for the Neurobiology of Learning and Memory, and Department of Neurobiology and Behavior, University of California, Irvine, California 92697-3800, USA. broozend@uci.edu
Phillips
R G
RG
Power
A E
AE
Brooke
S M
SM
Sapolsky
R M
RM
McGaugh
J L
JL
D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D003345:Corticosterone / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006624:Hippocampus / Q000293:injuries / Q000503:physiopathology* / Q000601:surgery; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D007608:Kainic Acid; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D008568:Memory / Q000502:physiology; D008569:Memory Disorders / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D009410:Nerve Degeneration / Q000139:chemically induced / Q000503:physiopathology; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D009434:Neural Pathways / Q000293:injuries / Q000503:physiopathology / Q000601:surgery; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000503:physiopathology*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology
D011725:Pyridines; C013109:metapyrone; D007608:Kainic Acid; D003345:Corticosterone