Intensity matters : effects of prenatal stress on the developing brain / Richelle Mychasiuk

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Mychasiuk, Richelle
University of Lethbridge. Faculty of Arts and Science
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Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2010
This thesis examines the behavioral, structural, cellular, and epigenetic changes observed in offspring exposed to different prenatal stressors. A number of questions were answered in this thesis that contribute to a basic understanding of the mechanisms by which early experiences alter long-term outcomes. These include: 1) What epigenetic modifications are associated with prenatal stress? 2) What are the structural and cellular changes in the brains of offspring that correspond to prenatal stress exposure? 3) How do these epigenetic and structural changes manifest as behavioral changes? And 4) What are the consequences of varying the level of prenatal stress?The key findings were that not all prenatal stress is the same. Variations to the intensity and nature of the stress dramatically alter offspring outcomes. Second, prenatal stress produces changes at many levels and these changes can be functionally related. Expression changes were identified in genes involved in altering dendritic morphology, which in turn modifies behaviour. For the first time, a comprehensive examination of brain plasticity occurred following prenatal stress. Additionally, this thesis demonstrated that brain changes related to prenatal stress are age-dependent and sex-dependent. The effects of prenatal stress on the pre-weaning brain are dramatically different than those observed in adulthood. Also, the sex of the offspring significantly influences neuroanatomical and epigenetic modifications. This finding is of critical importance because a majority of prenatal stress research is conducted on male offspring only. Taken together these discoveries emphasize that perturbations to development during the prenatal period produce persistent changes in the structure and functioning of the brain that will influence all subsequent experiences
xx, 201 leaves ; 29 cm
Brain -- Effect of stress on , Prenatal influences , Stress (Physiology) , Rats (Behavior) , Dissertations, Academic