Modulation of social learning in rats by brain corticotropin-releasing factor.
In order to investigate the impact of brain stress-related neuropeptide tone on learning and memory performance, juvenile recognition ability was examined in adult female rats using a social memory test following pharmacological inactivation and activation of corticotropin-releasing factor (CRF) systems. In particular, administration of a competitive CRF receptor antagonist [0.2, 1 or 5 microg intracerebroventricular doses of D-Phe CRF (12-41)], dose dependently impaired learning performance over a 30-min delay to 27% of vehicle controls values. In complementary fashion, forgetting produced by a 120-min delay that impaired social recognition performance to 29% of 30-min delay control levels was reversed by administration of a 1-microg dose of the CRF binding protein ligand inhibitor, r/h CRF (6-33), although a higher 5 microg dose exerted non-specific effects on social investigation. These findings suggest that brain CRF systems are physiologically relevant for social memory capacity in the absence of stressor exposure.
Heinrichs
Stephen C
SC
Department of Psychology, Boston College, McGuinn Hall 412, 140 Commonwealth Avenue, Chestnut Hill, MA 02467-3800, USA. stephen.heinrichs@bc.edu
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051381:Rats; D012919:Social Behavior
D003346:Corticotropin-Releasing Hormone