| Project/Area Number |
17590198
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Environmental physiology (including Physical medicine and Nutritional physiology)
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| Research Institution | University of Yamanashi |
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Principal Investigator |
ARITA Jun University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Professor, 大学院医学工学総合研究部, 教授 (80128587)
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| Co-Investigator(Kenkyū-buntansha) |
ISHIDA Maho University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, tesearch Associate, 大学院医学工学総合研究部, 助手 (80362086)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2006: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2005: ¥2,200,000 (Direct Cost: ¥2,200,000)
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| Keywords | estrogen / cell proliferation / anterior pituitary gland / CREB |
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| Research Abstract |
1 We generated Ad-TRE/MCREB.Tag, an adenovirus vector expressing the dominant negative CREB mutant MCREB. We verified morphologically and functionally the expression of MCREB protein.
2 Infection with Ad-TRE/bgal as a negative control did not change forskolin-induced proliferation of lactotrophs whereas Ad-TRE/MCREB.Tag infection completely blocked forskolin-induced proliferation.
3 Infection with Ad-TRE/MCREB.Tag partially suppressed stimulation of lactotroph proliferation by insulin-like growth factor-1 (IGF-1), a mitogen whose action is mediated by a signaling pathway distinct from the cyclic AMP/protein kinase A pathway.
4 Treatment with forskolin or estradiol alone increased prolactin promoter activity and their combination further increased the promoter activity. Infection with Ad-TRE/bgal did not change basal or forskolin-induced levels of prolactin promoter activity whereas Ad-TRE/MCREB.Tag infection partially suppressed the basal and forskolin-induced levels.
5 Intracellular cyclic AMP levels were markedly increased by forskolin treatment but not by IGF-1 treatment. Forskolin treatment markedly increased the proportion of phosphorylated CREB-immunoreactive lactotrophs at 20 min and up to 9 h whereas IGF-1 treatment modestly increased it only at 20 min and 1 h.
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