Effect of early life stress on locomotion and corticosterone in peripheral blood in adult rats

Abstract

Objective To investigate the effect of early life stress on the locomotion and concentration of corticosterone in peripheral blood in adult rats.Methods Maternal deprivation and isolation were used in the model of early life stress. Chronic stress was used in adult rats.Open field test was used for the measurement of locomotion activity. ELISA was used to measure the concentration of corticosterone in peripheral blood.Results The total activity time of locomotion[(296.96±6.63)s, (291.06±8.40)s;P＜0.01] and the concentration of corticosterone [(15.51±2.41)nmol/L,(11.27±2.49)nmol/L;P＜0.05]were increased in adult rats by maternal deprivation. The total activity distance [(23231.29±2030.35)mm,(14042.81.06±2875.34)mm;P＜0.05] and time[(296.39±3.48)s,(259.18±4.71)s;P＜0.01]were increased after chronic stress which was used in adult rats in which maternal deprivation were used before. The concentration of corticosterone[(20.60±1.83)nmol/L,(14.49±1.37)nmol/L;P＜0.01]was also increased in the same condition.Conclusions The concentration of corticosterone and locomotion activity of adult rats can be increased by early life stress. The reaction of HPA axis for chronic stress was improved by early life stress. Key words: Early life stress; Maternal deprivation; Locomotion; Corticosterone; HPA axis