Effects of maternal cadmium administration on development of monoaminergic, GABAergic and glutamatergic systems.

The effects of maternal exposure to 10mgCd/l (as cadmium acetate) in drinking water during gestation and lactation on the development of monoaminergic and aminoacidergic systems were studied in discrete brain areas of the pups: striatum, cerebral cortex, dorsal hippocampus and basal-medial hypothalamus. Hippocampal levels of serotonin and 5-hydroxyindolacetic acid were significantly reduced in rats exposed to Cd whereas the dopamine content was not significantly affected by Cd. Glutamate concentration decreased in hypothalamus and increased in hippocampus, while gamma-aminobutiric acid content decreased only in cerebral cortex.

Influence of metyrapone treatment during pregnancy on the development and maturation of brain monoaminergic systems in the rat.

Aim: This study examines the effect of reducing the corticosterone levels of gestating rat dams on the postnatal development and maturation of monoaminergic systems in their offspring's brains.

Methods: Metyrapone, an inhibitor of CORT synthesis, was administered to pregnant rats from E0 to E17 of gestation. Monoamine concentrations were determined in male and female offspring at postnatal days (PN) 23 and 90 in the hippocampus, hypothalamus and striatum.

Role of maternal corticosterone in the development and maturation of the aminoacidergic systems of the rat brain.

Previous studies have suggested an important role for maternal glucocorticoids in the development of the aminoacidergic systems of the rat brain. This study examines the effect of metyrapone (2-methyl-1,2-di-3-pyridyl-1-propanone), i.p.

Effect of intrauterine position on sex differences in the gabaergic system and behavior of rats.

In multiparous species such as the rat (in this case the albino Wistar strain), steroid influence during fetal growth is affected by the relative intrauterine position of male and female fetuses and is stronger when the potential effects of contiguity and caudal position are combined. The effect of intrauterine position on gonadal steroid levels in neonatal and adult animals was examined using radioimmunoassay techniques. Since the organizing effect of prenatal steroids may influence the postnatal GABA content, HPLC was used to determine the gabaergic content in several hypothalamic and limbic areas in the adult rat.

Effect of 17-beta-estradiol on dopamine, serotonine and GABA striatal levels in 6-hydroxydopamine-treated rats.

Intrastriatal injection (16microg) of the neurotoxic dopaminergic agent 6-hydroxydopamine (6-OHDA) in ovariectomized rats caused important reductions in striatal dopamine (DA) and serotonin (5-HT) levels and an increase in GABA content. Treatment of ovariectomized rats with estradiol (5 mg 17-beta-estradiol administered by a subcutaneous cannula) before 6-OHDA injection maintained the control levels of these neurotransmitters. The administration of estradiol after 6-OHDA injection did not lead to their recovery.