| Autor: |
Powers, B. E., Lin, T.-M., Vanka, A., Peterson, R. E., Juraska, J. M., Schantz, S. L. |
| Předmět: |
|
| Zdroj: |
Genes, Brain & Behavior; Feb2005, Vol. 4 Issue 1, p51-59, 9p, 1 Diagram, 2 Charts, 4 Graphs |
| Abstrakt: |
Perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter spatial learning in rats tested on a radial arm maze (RAM). TCDD is believed to exert most of its effects through binding to the aryl hydrocarbon receptor (AhR). To determine whether the AhR mediates TCDD-induced alterations in spatial learning, we tested male and femaleAhR-knockout (AhR –/–), heterozygous (AhR +/–) and wild-type (AhR +/+) mice on the RAM.AhR +/– male and female mice were time mated, and treated dams were dosed with 5 μg TCDD/kg body weight on day 13 of gestation. When offspring reached adulthood, male and femaleAhR +/+,AhR +/– andAhR –/– mice from TCDD-exposed and unexposed litters were tested on the eight-arm RAM. After testing, we examined hippocampal morphology as visualized by the Timm's silver sulfide stain. TCDD-exposed femaleAhR +/– mice made more errors than their respective controls on the RAM and exhibited a decrease in the size of the intra- and infrapyramidal mossy fiber (IIP-MF) field of the hippocampus. None of the other TCDD-exposed groups differed from their respective control groups with regard to maze performance or hippocampal morphology. The reduction of IIP-MF field indicates a possible morphological basis for the learning deficit that was observed in the femaleAhR +/– mice. It is hypothesized that the effect of TCDD exposure is AhR dependent and that TCDD may alter GABAergic activity in the hippocampus of female mice during development. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
