Prenatal stressors in rodents: Effects on behavior

Area of Science:

• Neuroscience
• Developmental Psychology
• Behavioral Biology

Background:

• Maternal stress during gestation is linked to behavioral abnormalities in human offspring.
• Rodent models replicate some of these human behavioral issues, including anxiety, depression, and social deficits.

Purpose of the Study:

• To review rodent studies published since 2008 on the effects of prenatal stress on offspring behavior.
• To explore reasons for observed differences in behavioral outcomes.
• To investigate the neurobiological underpinnings of these behavioral changes.

Main Methods:

• Review of rodent studies examining behavioral tests (elevated plus maze, open field, forced swim, sucrose preference, social interaction, Morris water maze, novel object recognition).
• Analysis of neurobiological markers, including hippocampal glutamate receptors (NR2B) and brain-derived neurotrophic factor (BDNF).
• Examination of epigenetic mechanisms, such as gene methylation, in response to prenatal stress.

Main Results:

• Prenatal stress in rodents induces anxiety, depression-like behaviors, and social interaction deficits.
• Spatial learning and memory impairments were observed, primarily in male rodents.
• Reduced hippocampal NR2B and BDNF levels were correlated with learning deficits and decreased long-term potentiation.
• Down-regulation of BDNF in mice involved increased gene-methylating enzymes.

Conclusions:

• Rodent data support a physiological basis for the neurodevelopmental hypothesis of schizophrenia and depression.
• Prenatal stress significantly impacts offspring neurodevelopment and behavior.
• Epigenetic modifications, like DNA methylation, may mediate the effects of prenatal stress on BDNF levels.