Maternal care counteracts behavioral effects of prenatal environmental stress in female rats.

There is extensive evidence in rats that prenatal environmental stress (PES) exposure and early postnatal altered maternal care, as a consequence of stress during gestation, can detrimentally affect the brain and behavioral development of the offspring. In order to separate the effect of PES on the fetuses from that on the behavior of the mother, in the present study, we used a cross-fostering procedure in which PES-fetuses were raised by non-stressed mothers and non PES-fetuses were raised by stressed mothers. In Experiment 1, non-stressed mothers showed significantly more maternal behavior than stressed mothers. In Experiment 2, when the female offspring from Experiment 1 reached maturity, they were tested for: (1) induced maternal behavior (MB), (2) plasma levels of corticosterone (Cpd B), progesterone (P), and estradiol (E(2)), (3) number of accessory olfactory bulb (AOB) mitral cells, and (4) c-fos expression measured in AOB and medial preoptic area (MPOA) neurons. We replicated our previous findings that the PES group reared by their own stressed mothers, when adult, attacked the young, expressed disorganized MB and showed altered Cpd B, P and E(2) levels, plus a male-like neuro-morphological pattern in the AOB, by comparison with the non-PES group, reared by their own non-stressed mothers. By contrast, when adult, the PES group reared by non-stressed mothers showed hormonal and morphological neuronal alterations, but they displayed appropriate (full) MB. The non-PES group raised by stressed mothers also showed altered hormone levels, but showed full MB and no morphological neuronal changes. Significant differences in the AOB and MPOA c-fos activity, related to whether or not MB was expressed, were found in the non-PES groups, but not in the PES group reared by non-stressed mothers. To our knowledge, this is the first study to document that adequate maternal care, early in development, can shape the subsequent expression of induced MB, overcoming neuro-morphological and hormonal alterations that are produced by prenatal environmental stress. We conclude that maternal care during early postnatal development can counteract detrimental effects of prenatal environmental stress, exerting long-lasting effects that modulate the behavioral phenotype of the offspring.

Del Cerro MC ，Pérez-Laso C ，Ortega E ，Martín JL ，Gómez F ，Pérez-Izquierdo MA ，Segovia S ... -  《-》

Environmental prenatal stress alters sexual dimorphism of maternal behavior in rats.

Pérez-Laso C ，Segovia S ，Martín JL ，Ortega E ，Gómez F ，Del Cerro MC ... -  《BEHAVIOURAL BRAIN RESEARCH》

Prenatal stress and early adoption effects on benzodiazepine receptors and anxiogenic behavior in the adult rat brain.

Barros VG ，Rodríguez P ，Martijena ID ，Pérez A ，Molina VA ，Antonelli MC ... -  《SYNAPSE》

Maternal care interacts with prenatal stress in altering sexual dimorphism in male rats.

The present study analyzes the interaction between prenatal stress and mother's behavior on brain, hormonal, and behavioral development of male offspring in rats. It extends to males our previous findings, in females, that maternal care can alter behavioral dimorphism that becomes evident in the neonates when they mature. Experiment 1 compares the maternal behavior of foster mothers toward cross-fostered pups versus mothers rearing their own litters. Experiment 2 ascertains the induced "maternal" behavior of the male pups, derived from Experiment 1 when they reached maturity. The most striking effect was that the males non-exposed to the stress as fetuses and raised by stressed foster mothers showed the highest levels of "maternal" behavior of all the groups (i.e., induction of maternal behavior and retrieving behavior), not differing from the control, unstressed, female groups. Furthermore, those males showed significantly fewer olfactory bulb mitral cells than the control males that were non-stressed as fetuses and raised by their own non-stressed mothers. They also presented the lowest levels of plasma testosterone of all the male groups. The present findings provide evidence that prenatal environmental stress can "demasculinize" the behavior, brain anatomy and hormone secretion in the male fetuses expressed when they reach maturity. Moreover, the nature of the maternal care received by neonates can affect the behavior and physiology that they express at maturity.

Pérez-Laso C ，Ortega E ，Martín JL ，Pérez-Izquierdo MA ，Gómez F ，Segovia S ，Del Cerro MC ... -  《-》

Effects of maternal corticosterone and stress on behavioral and hormonal indices of formalin pain in male and female offspring of different ages.

Butkevich I ，Mikhailenko V ，Semionov P ，Bagaeva T ，Otellin V ，Aloisi AM ... -  《-》