Involvement of amygdaloid corticosterone in altered visceral and somatic sensation

Behavioral responses to thermal and mechanical stimuli were used to examine somatic sensitivity in rats with stereotaxic corticosterone (CORT) implants on the amygdala. These animals have previously been shown to display anxiety-like behavior coupled with colonic hypersensitivity; in this study, CORT induced not only visceral hypersensitivity but also somatic hypersensitivity. These findings suggest that modulation of the amygdala with CORT results in a generalized decrease in sensory thresholds via descending neuronal pathways. (c) 2007 Elsevier B.V. All rights reserved.