Acute corticosterone treatment is sufficient to induce anxiety and amygdaloid dendritic hypertrophy

作者:Mitra Rupshi*; Sapolsky Robert M
来源:Proceedings of the National Academy of Sciences of the United States of America, 2008, 105(14): 5573-5578.
DOI:10.1073/pnas.0705615105

摘要

Stress is known to induce dendritic hypertrophy in the basolateral annygdala (BLA) and to enhance anxiety. Stress also leads to secretion of glucocorticoids (GC) and the BLA has a high concentration of glucocorticoid receptors. This raises the possibility that stress-induced elevation in GC secretion might directly affect annygdaloid neurons. To address the possible effects of GC on neurons of amygdala and on anxiety, we used rats treated either acutely with a single dose or chronically with 10 daily doses of high physiological levels of corticosterone (the rat-specific glucocorticoid). Behavior and morphological changes in neurons of BLA were measured 12 days after the initiation of treatment in both groups. A single acute dose of corticosterone was sufficient to induce dendritic hypertrophy in the BLA and heightened anxiety, as measured on an elevated plus maze. Moreover, this form of dendritic hypertrophy after acute treatment was of a magnitude similar to that caused by chronic treatment. Thus, plasticity of BLA neurons is sufficiently sensitive so as to The saturated by a single day of stress. The effects of corticosterone were specific to anxiety, as neither acute nor chronic treatment caused any change in conditioned fear or in general locomotor activity in these animals.

  • 出版日期2008-4-8