[Long-term effects of stress in critical periods of development on reactivity of adult female rats].

Effects of stress during different periods of ontogeny, namely, the prenatal, prepubertal, or their combination (prenatal+prepubertal), on the indices of psychoemotional and tonic pain-related behaviors, as well as corticosterone reactivity after pain behavior were investigated in adult 90-day-old female Wistar rats. Our data show for the first time, the similarity of effects of prenatal (immobilization stress of a rat dam during the last week of pregnancy) and prepubertal (forced swimming, pain-related response in the formalin test) stresses on the indices under study, an increase in the time of immobility and in licking duration, but the difference between effects of combined stress on these indices. Pain-related response increased corticosterone in prepubertally stressed rats while in prenatally stressed rats, decreased it. In rats experienced combined stress, formalin-induced pain increased corticosterone as compared with that in prenatally, but not in prepubertally stressed rats. A positive correlation between pain-related reaction and stressed hormonal response was revealed in prepubertally stressed animals. So, long-term effects of stress during critical periods of ontogeny determine stress reactivity of behavioral and hormonal responses in adult female rats.