Prenatal sound stress increases anxiety behvaiour of rat's male offspring

Presence of stressors during the last weeks of gestation has been associated with behavioral disorders in the offspring. The aim of the present study is to determine if prenatal exposure with noise affects anxiety in adult offspring. Three groups of pregnant rats were exposed to daily noise stress with durations of 1, 2 and 4 hour(s)/day from day 15 to 21 of gestation. A forth group was left undisturbed during pregnancy. Using elevated plus maze (EPM), their offspring's anxiety behavior were studied when 45 day old (n=10 in each group). Percentage of entries and time spent in open arms over the total exploration in both open and closed arms were calculated. Also, total serum corticosterone of dams and offspring were measured. We found that applying noise stress (2 and/or 4 hours) in late gestation increased anxiety behavior in the offspring (P<0.05); also, their total corticosterone concentration were higher than the control group. The anxiety behavior and corticosterone level of offspring with one hour noise stress was similar to that of controls. ‍ Applying noise stress on pregnant rats increased anxiety behavior and total corticosterone level of their offspring, but the incidence of these alterations depended on duration of the sound stress.