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Prenatal bystander stress induces neuroanatomical changes in the prefrontal cortex and hippocampus of developing rat
Richelle Mychasiuk1, Robbin Gibb, Bryan Kolb
1Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Canada. R.mychasiuk@uleth.ca
Insights
Prenatal bystander stress significantly altered brain development in young rats. This stress impacted dendritic structure, spine density, and cell numbers in key brain regions, affecting maturation.
Area of Science:
- Neuroscience
- Developmental Biology
- Neurodevelopmental Disorders
Background:
- Prenatal development is critical for brain formation.
- Cortical plasticity is vulnerable to disruptions during this period.
- Limited research exists on the effects of prenatal stress on young, developing brains.
Purpose of the Study:
- To investigate the neuroanatomical consequences of indirect prenatal bystander stress.
- To analyze changes in the developing brain of postnatal day 21 (P21) Long Evans rats.
Main Methods:
- Utilized an indirect prenatal bystander stress model in rats.
- Quantified dendritic architecture (length, branch order, spine density) of layer 3 pyramidal cells.
- Assessed cell quantification (neuron and glia) in the medial prefrontal cortex (mPFC), orbital prefrontal cortex (OFC), and hippocampus (CA1).
Main Results:
- Prenatal stress significantly altered dendritic complexity and length.
- Excitatory spine density was notably affected by the stress.
- Neuronal and glial cell numbers and volume were significantly changed in the mPFC, OFC, and CA1.
Conclusions:
- Prenatal bystander stress induces significant neuroanatomical alterations in the developing brain.
- These changes during a critical developmental window likely impact healthy brain maturation.
- Findings suggest potential long-term consequences for neurodevelopmental trajectories.
Abstract:
The rapid period of growth and development that occurs prenatally renders the brain vulnerable to experiences that may disrupt cortical plasticity. Although there is extensive literature examining anatomical changes in fully matured brain, there has been very little investigation of younger offspring. The current study used an indirect prenatal bystander stress and analyzed neuroanatomical changes in postnatal day 21 (P21) Long Evans rats. Dendritic architecture (dendritic length, branch order, and spine density) along with cell quantification (neuron and glia) was generated for layer 3 pyramidal cells of the medial prefrontal cortex (mPFC/Cg3), orbital prefrontal cortex (OFC/AID), and CA1 of the hippocampus. We found that prenatal bystander stress significantly altered the complexity and length of dendritic arbor, the density of excitatory spines and the actual volume of neuronal and glial cell numbers in the mPFC, OFC, and CA1 of developing rat offspring. Neuroanatomical changes of this extent occurring at such a critical time period will likely impact healthy maturation of the brain and long-term development.
