Corticosterone controls the developmental emergence of fear and amygdala function to predator odors in infant rat pups

• DOI: 10.1016/j.ijdevneu.2004.05.011
• Publication Date: 2004-08-05T00:12:11Z
• Authors: Stephanie Moriceau; Tania L. Roth; Terri Okotoghaide; Regina M. Sullivan
• Keywords: Corticosterone; Basolateral amygdala; Altricial

Abstract In many altricial species, fear responses such as freezing do not emerge until sometime later in development. infant rats, to natural predator odors emerges around postnatal day (PN) 10 when rats begin walking. The behavioral emergence of is correlated with two physiological events: functional the amygdala and increasing corticosterone (CORT) levels. Here, we hypothesize that levels influence activity permit expression. We assessed relationship between expression (immobility similar freezing), function (c‐fos) level pups response presentation novel male odor (predator), littermate no odor. CORT were increased PN8 (no fear, normally low CORT) by exogenous (3 mg/kg) decreased PN12 (express higher) through adrenalectomy replacement. Results showed a basolateral/lateral could be prematurely evoked CORT, while prevented both activation. These results suggest neonatal serves protect from responding inducing stimuli attenuate This suggests alteration system environmental insults alcohol, stress illegal drugs, may also alter its underlying neural control.