Raising babies is a stressful thing, made even more so when Mom herself is raised: a meter high on a Plexiglas platform, while she’s pregnant, that is. The effect on her kids – er, pups – is manifest in brain and body weight, in behavioral development, and even epigenetically.
Researchers from the University of Lethbridge in Alberta, Canada put pregnant rats up on a small see-through platform for 10 or 30 minutes twice daily, and looked at how that mild or high stress (respectively) expresses itself in the neonates.
Mom’s stress definitely took its toll (on both her and her pups), with mild and high stress sometimes having opposite effects, and males and females sometimes being differentially affected as well:
- Pups of both sexes that had been subject to mild stress in utero showed increased global levels of DNA methylation in the hippocampus, and in the frontal cortex of males.
- High prenatal stress reduced global methylation levels in the hippocampus and frontal cortex of both sexes.
- Mild stress decreased the body weight and brain weight of both sexes. But highly stressed males had decreased brain weight while that of the females was increased.
- Mild stress pups performed worse on a test for early sensorimotor development. Highly stress pups didn’t show any deficits at postnatal day 9, but didn’t improve (compared to controls) on day 10.
Want more details? Don’t stress it – you can find them at Neuroscience February 2011