Characteristics of the Behavior and Stress-Reactivity of the Hypophyseal-Adrenal System in Prenatally Stressed Rats

Abstract

The effects of daily 1-h immobilization of female rats from days 15 to 18 of pregnancy on the levels of anxiety, orientational-investigative activity in an open field test, and the dynamics of the stress response of the hypophyseal-adrenal system were studied in the male and female adult offspring of these rats. Maternal stress was found to induce significant reductions in the level of orientational-investigative activity of females in the stage of diestrus, and to increase anxiety as measured in an elevated cross maze. Prenatally stressed males, conversely, had decreased levels of anxiety, and behavior in the open field test was virtually unaltered. As a result, prenatally stressed rats showed smoothing out of the intergender differences in these forms of behavior, seen in control animals in normal conditions. Prenatal stress had a significant influence on the dynamics of the stress response of the hypophyseal-adrenal system in males and females; males showed impairment of the feedback control of this system in conditions of stress activation, while females showed significant increases in the maximum level of adrenal corticosterone secretion into the blood in response to immobilization lasting 20 min. These data provide evidence that maternal stress has significant influences on behavior and the stress response in both male and female rats.

Prenatal stress diminishes gender differences in behavior and in expression of hippocampal synaptic genes and proteins in rats

“…This suggests that prenatal stress may alter the sensitivity of hippocampal receptors to estradiol or other neuroactive steroids. Irrespective of the stage of the estrous cycle, prenatal stress abolished the difference in anxiogenic behavior in the two sexes as shown in other studies (Fride and Weinstock, 1988;Ordyan and Pivina, 2004).…”

Sex differences in salivary cortisol in response to acute stressors among healthy participants, in recreational or pathological gamblers, and in those with posttraumatic stress disorder

“…A reciprocal relationship between pharmacological addiction and HPA activation may exist, such that stress and HPA activation promote the likelihood of use (Goeders 1997, 2002ab), and use alters HPA arousal. Indeed, research in animal models indicates that early stress experiences alter HPA response throughout life such that HPA hormones can be down-regulated while ligand targets can be upregulated and these effects are sex-dependent with males attenuating and females hyper-activating HPA response (Bosch et al, 2007; Mabandla et al, 2007; Ordyan and Pivina, 2004). As well, reinforcing properties of hedonic stimuli can be enhanced by early stress (Kippin et al, 2007).…”

Altered brain activity processing in high-anxiety rodents revealed by challenge paradigms and functional mapping

“…Indeed, it was shown in a number of studies that prenatal stress induces high anxiety in offspring as revealed by tests including the EPM, open field, and social interaction in rats (e.g. Vallee et al, 1997;Estanislau and Morato, 2005) and mice (Chung et al, 2005), while only a few studies have found no effect (Ordyan and Pivina, 2004). The early postnatal period and the bond between mother and infant seems particularly important in the development and shaping of normal emotional behavior (for recent reviews see Holmes et al, 2005;Pryce et al, 2005).…”