2007 Fiscal Year Final Research Report Summary
Sensitive assay for disturbance of brain function by environmental pollutants at low concentrations
| Project/Area Number |
18510058
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Risk sciences of radiation/Chemicals
|
|---|
| Research Institution | Hiroshima University |
|---|
Principal Investigator |
YAMAZAKI Takeshi Hiroshima University, Graduate School of Integrated Arts and Sciences, Professor (30192397)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SAKATA Syogo Hiroshima University, Graduate School of Integrated Arts and Sciences, Professor (50153888)
|
|---|
| Project Period (FY) |
2006 – 2007
|
| Keywords | environmental pollution / tributyltin / working memory / estradiol / neurosteroid |
|---|
| Research Abstract |
Tributyltin induced increase in cytochromes P45017α and P450arom in cultures rat hippocampal slices. This treatment also induced increase in biosynthesis of testosterone and estradiol 17β. Since tributyltin can activate RXR-mediating cellular response, we determined action of RXR on neuronsteroidogenesis in the hippocampus. 9-cis Retinoic acid, an agonist for RXR, stimulated estradiol synthesis and mRNA contents for P450 17α in cultured rat hippocampus. These results indicate that the action of tributyltin on hippocampal steroidogenesis was mediated by RXR.
Direct injection of tributyltin in adult rat hippocampus induced increase in mRNA for P450 17α. Estradiol content of the hippocampus, however, was not affected, although the treatment with tributyltin may stimulate testosterone biosynthesis in the hippocampus. Castration of the rat induced significant decrease in testosterone contents in brain and serum. Estradiol content in the castrated rat hippocampus was the same as that in the non-treated rat. These data indicate that the estradiol content in the hippocampus was independent from testosterone content and synthesis in the hippocampus.
|
