Prenatal stress alters limbo-corticostriatal Homer protein expression.

Early environmental stress influences developmental processes resulting in alterations in behavior and brain function, including abnormalities in glutamate neurotransmission. Here, we assessed the influence of prenatal stress on limbo-corticostriatal expression of Homer proteins that are critical elements in glutamatergic signaling. Pregnant, female Sprague-Dawley rats were subjected to either no treatment or to restraint stress 3 times per day for the last 7 days of gestation. At 21 d of age, offspring were sacrificed and brain tissue was rapidly extracted. Immunoblotting revealed regionally specific increases in certain Homer protein isoforms within prefrontal cortex and limbic structures, whereas the striatum exhibited a reduction in Homer 1a levels. These findings indicate that stress during development can produce enduring perturbations in Homer protein expression that likely contribute to glutamatergic and behavioral abnormalities observed following early environmental stress. (c) 2007 Wiley-Liss, Inc.