Maternal psychosocial stress during early gestation impairs fetal structural brain development in sheep.

Maternal stress, especially during early pregnancy, predisposes offspring to neuropsychiatric disorders. We hypothesized that maternal psychosocial stress (MPS) during pregnancy affects fetal structural neurodevelopment depending on the gestational age of exposure. Fetal sheep brains were harvested at 130 days gestation (dG, term 150 dG) from ewes frequently isolated from flock-mates during early gestation (first and second trimester;  = 10) or late gestation (third trimester;  = 10), or from control flock-mates ( = 8).

Cardiovascular effects of prenatal stress-Are there implications for cerebrovascular, cognitive and mental health outcome?

Prenatal stress programs offspring cognitive and mental health outcome. We reviewed whether prenatal stress also programs cardiovascular dysfunction which potentially modulates cerebrovascular, cognitive and mental health disorders. We focused on maternal stress and prenatal glucocorticoid (GC) exposure which have different programming effects.

Fetal Sheep Mesenteric Resistance Arteries: Functional and Structural Maturation.

Background: Fetal blood pressure increases during late gestation; however, the underlying vascular mechanisms are unclear. Knowledge of the maturation of resistance arteries is important to identify the mechanisms and vulnerable periods for the development of vascular dysfunction in adulthood.

Methods: We determined the functional and structural development of fetal sheep mesenteric resistance arteries using wire myography and immunohistochemistry.

Modification of the ladder rung walking task-new options for analysis of skilled movements.

Method sensitivity is critical for evaluation of poststroke motor function. Skilled walking was assessed in horizontal, upward, and downward rung ladder walking to compare the demands of the tasks and test sensitivity. The complete step sequence of a walk was subjected to analysis aimed at demonstrating the walking pattern, step sequence, step cycle, limb coordination, and limb interaction to complement the foot fault scoring system.

Vulnerability of the fetal primate brain to moderate reduction in maternal global nutrient availability.

Moderate maternal nutrient restriction during pregnancy occurs in both developing and developed countries. In addition to poverty, maternal dieting, teenage pregnancy, and uterine vascular problems in older mothers are causes of decreased fetal nutrition. We evaluated the impact of global 30% maternal nutrient reduction (MNR) on early fetal baboon brain maturation.

Adverse effects of antenatal glucocorticoids on cerebral myelination in sheep.

Objective: To determine in fetal sheep the effect of betamethasone on myelination in relation to stage of myelination, number of treatment courses, dose, and route of administration.

Methods: Fetal expression of myelin basic protein (MBP), a marker of mature oligodendrocytes and myelin, was determined between 0.27 and 0.

Betamethasone-related acute alterations of microtubule-associated proteins in the fetal sheep brain are reversible and independent of age during the last one-third of gestation.

Objective: The purpose of this study was to examine whether glucocorticoid effects on neuronal cytoskeleton, which we have shown previously at 0.87 gestation when the hypothalamo-pituitary-adrenal axis matures, are age-dependent and reversible.

Study Design: Fetal sheep received 3.

Lack of effect of antenatal glucocorticoid therapy in the fetal baboon on cerebral cortical glucose transporter proteins.

Background: Maternal antenatal glucocorticoid therapy is used to accelerate lung maturation of immature babies at risk of preterm delivery. It acutely affects brain activity of the human fetus and reduces the immunoreactivity of neurocytoskeletal and synaptic proteins in the fetal baboon brain. These effects might be based on cerebral energy failure due to a decreased neuronal glucose uptake that has been shown in vitro.

Glucose transporter proteins GLUT1 and GLUT3 like immunoreactivities in the fetal sheep brain are not reduced by maternal betamethasone treatment.

Synthetic glucocorticoids administered to accelerate fetal lung maturation in threatened preterm delivery change electrocortical brain activity in the human and sheep fetus and alter structural neuronal proteins in fetal baboon and sheep. We hypothesized that these changes are due to a decreased amount of glucose transporter proteins (GLUT). Glucose uptake into cerebral neurons is selectively facilitated by glucose transporter protein GLUT1 in the blood brain barrier and GLUT3 in neuronal membranes.

Motor improvements after focal cortical ischemia in adult rats are mediated by compensatory mechanisms.

Initial functional impairments after cerebral ischemia often improve considerably during the early period after the insult. Although pathological changes associated with post-lesion improvements have been widely investigated, it has not been resolved whether behavioral improvement represents true restoration of function (recovery) or development of new strategies (compensation). This study investigated whether early motor improvements after focal cerebral ischemia reflect recovery or compensation.

Recovery of glucocorticoid-related loss of synaptic density in the fetal sheep brain at 0.75 of gestation.

Antenatal glucocorticoids routinely used to accelerate fetal lung maturation in human pregnancy at risk of preterm delivery decrease synaptic density and complex electrocortical activity in the fetal sheep brain at 0.87 gestation. We examined whether the effects of betamethasone on synaptic density depend on maturation of hypothalamo-pituitary-adrenal (HPA) axis and whether these effects are reversible.

Glucocorticoid exposure at the dose used clinically alters cytoskeletal proteins and presynaptic terminals in the fetal baboon brain.

Glucocorticoids have been used for 30 years to accelerate fetal lung maturation in human pregnancy at risk of preterm delivery. Exposure to inappropriate levels of steroid, however, leads to altered maturation of the cardiovascular, metabolic and central nervous systems. The effects of betamethasone on neuronal development and function were determined in the fetal baboon brain by examination of cytoskeletal microtubule associated proteins (MAPs) and the presynaptic marker protein synaptophysin.

Developmental changes in cerebral autoregulatory capacity in the fetal sheep parietal cortex.

We validated laser Doppler flowmetry (LDF) for long-term monitoring and detection of acute changes of local cerebral blood flow (lCBF) in chronically instrumented fetal sheep. Using LDF, we estimated developmental changes of cerebral autoregulation. Single fibre laser probes (0.