| Project/Area Number |
11694328
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A).
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
内科学一般
|
|---|
| Research Institution | Hyogo University |
|---|
Principal Investigator |
KITO Shozo Research Institute of Hyogo University, Professor, 附属研究所, 教授 (00010140)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HONZAWA Mayumi Hyogo College, Nutrition and Food Science, Professor, 短期大学部・食物栄養学科, 教授 (00132374)
NOMURA Yasuyuki Hokkaido University, Faculty of Pharmaceutical Science, Professor, 薬学部, 教授 (00034041)
TOHYAMA Masaya Osaka University, School of Medicine, Professor, 医学部, 教授 (40028593)
SHINGO Akiko Research Institute of Hyogo University, Assistant Professor, 附属研究所, 講師 (50309499)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Project Status |
Completed (Fiscal Year 2000)
|
| Budget Amount *help |
¥7,600,000 (Direct Cost: ¥7,600,000)
Fiscal Year 2000: ¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 1999: ¥4,000,000 (Direct Cost: ¥4,000,000)
|
|---|
| Keywords | hippocampus / H19-7 cells / IGF-1 / estrogen / tamoxifen / ICI182,780 / cAMP / Ca ion / 不死化 / エストロゲン / ICI182、780 |
|---|
| Research Abstract |
Experiments were done with use of the H19-7 cell, the immortalized rat fetal hippocampal neural cell line which was established by transduction of a temperature-sensitive SV 40 large T antigen. The H19-7 cell was differentiated into neurons expressing neuronal markers at the nonpermissive temperature (39℃) in defined medium by several agents, including basic fibroblast growth factor (bFGF).
It was observed by RNase Protection assay that 10^<-9>M βestradiol increased IGF-1 mRNA expression in the differentiated H19-7 neuronal cell with was inhibited by simultaneous addition of tamoxifen, a partial antagonist of estrogen.
On the other hand, the effects of βestradiol on nuclear estrogen receptorα (ER α) mRNA expression in the differentiated H19-7 cell was observed by RNase Protection Assay. As the result, administration of 10^<-9>M βestradiol significantly increased expression of ER αmRNA showing estrogen-induced ER up-regulation that was inhibited by ICI182,780, but not by tamoxifen.
We conf
… More
irmed that βestradiol caused an increase of immediate and transient intracellular Ca ion concentration in the differentiated H19-7 neuronal cell suggesting existence of the membranous estrogen receptor. It has been advocated that the membrane receptor of estrogen is ligand-dependently conjugated with G-protein. It is assumed that thus increased cyclic AMP causes an increase of intracellular Ca ion concentration through the cyclic AMP-gated channel. Accordingly, we tried to observe the time course of intracellular protein kinase A (PKA) activity in the living differentiated H19-7 neuronal cell by the method of Kudo et al in which DR2 was used as fluorescent PKA indicator. We confirmed that estrogen induced an immediate increase of intracellular PKA activity in H19-7 neuronal cells. Moreover, we noticed that estrogen caused increases of AP-1, CREB binding activities and increases of GAP43 mRNA expression in the H19-7 neuronal cells by means of gel shift assay and real time PCR-based RNA analysis, respectively together with induction of IGF-1 mRNA expression. These estrogen-induced responses in H19-7 neuronal cells including expressions of IGF-1, GAP43 mRNAs and increases of CREB, AP-1 binding activities were all inhibited by simultaneous administration of ICI182,780. Less
|
