Transgenerational effects of social stress on social behavior, corticosterone, oxytocin, and prolactin in rats

Abstract

Social stressors such as depressed maternal care and family conflict are robust challenges which can have long-term physiological and behavioral effects on offspring and future generations. The current study investigates the transgenerational effects of an ethologically relevant chronic social stress on the behavior and endocrinology of juvenile and adult rats. Exposure to chronic social stress during lactation impairs maternal care in F0 lactating dams and the maternal care of the F1 offspring of those stressed F0 dams. The overall hypothesis was that the male and female F2 offspring of stressed F1 dams would display decreased social behavior as both juveniles and adults and that these behavioral effects would be accompanied by changes in plasma corticosterone, prolactin, and oxytocin. Both the female and male F2 offspring of dams exposed to chronic social stress displayed decreased social behavior as juveniles and adults, and these behavioral effects were accompanied by decreases in basal concentrations of corticosterone in both sexes, as well as elevated juvenile oxytocin and decreased adult prolactin in the female offspring. The data support the conclusion that social stress has transgenerational effects on the social behavior of the female and male offspring which are mediated by changes in the hypothalamic-pituitary-adrenal axis and hypothalamic-pituitary-gonadal axis. Social stress models are valuable resources in the study of the transgenerational effects of stress on the behavioral endocrinology of disorders such as depression, anxiety, autism, and other disorders involving disrupted social behavior.

Keywords: Anxiety; Autism; Corticosterone; Early life stress; Oxytocin; Postpartum depression; Prolactin; Social behavior; Social stress; Transgenerational.

Fig. 1

Transgenerational effect of chronic social stress on juvenile social behavior. Both female (A) and male (B) juvenile offspring of dams exposed to early life stress exhibit reduced social behavior toward a same-sex conspecific compared to offspring of control dams. * = p < 0.05 compared to controls. Invest = investigation.

Fig. 2

Transgenerational effect of chronic social stress on adult social approach behavior. Adult female (A) and male (B) behavior toward a confined same-sex adult conspecific. * = p < 0.05 compared to controls.

Fig. 3

Transgenerational effect of chronic social stress on adult social interaction behavior. Social behavior exhibited by adult female (A) and male (B) offspring of dams exposed to early life stress is altered compared to offspring of control dams. * = p < 0.05 compared to controls. Invest = investigation.

Fig. 4

Transgenerational effect of chronic social stress on basal corticosterone concentrations. Juvenile (A), but not adult (B), basal plasma corticosterone (CORT; means +1SEM) concentrations are attenuated in the offspring of dams exposed to early life stress compared to offspring of control dams. * = p < 0.05 compared to controls.

Fig. 5

Basal plasma oxytocin (OXT; means + 1SEM) concentrations are elevated in female juvenile offspring of dams exposed to social stress compared to female juvenile offspring of control dams. * = p < 0.05 compared to controls.

Fig. 6

Basal plasma prolactin (PRL; means + 1SEM) concentrations are attenuated in adult female offspring of stressed dams, compared to adult females of control dams. * = p < 0.05 compared to controls.