Suppression of corticosterone synthesis alters the behavior of hippocampally lesioned rats.
The suppression of corticosterone synthesis with metyrapone (25 mg/kg) reduced the hyperactivity and altered the exploratory activity of hippocampally lesioned animals (HPC) in the open field to the level of cortical and sham controls (Experiment 1). In a second experiment, corticosterone (600 micrograms/kg) pretreatment 2 h, but not 1 h, before metyrapone partially restored the hyperactivity of HPC animals that had been decreased by the corticosteroid-suppressant drug. Alterations in exploratory behavior induced by metyrapone were also prevented by corticosterone pretreatment. The results suggest that the suppression of corticosterone in hippocampally lesioned animals produces a normalization of behavior that can be prevented by pretreatment with corticosterone.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003345:Corticosterone / Q000008:administration & dosage / Q000096:biosynthesis*; D005106:Exploratory Behavior / Q000187:drug effects; D006624:Hippocampus / Q000503:physiopathology*; D007274:Injections, Intraperitoneal; D008124:Locomotion / Q000187:drug effects; D008297:Male; D008797:Metyrapone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors
D003345:Corticosterone; D008797:Metyrapone