Project/Area Number |
11672254
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
応用薬理学・医療系薬学
|
Research Institution | YAMAGATA UNIVERSITY SCHOOL OF MEDICNE |
Principal Investigator |
ISHIHATA Akira Yamagata Univ., School of Med, Instructor, 医学部, 助手 (40232326)
|
Co-Investigator(Kenkyū-buntansha) |
KATANO Yumi Yamagata Univ., School of Med, Professor, 医学部, 教授 (70018696)
|
Project Period (FY) |
1999 – 2000
|
Project Status |
Completed (Fiscal Year 2000)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2000: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1999: ¥2,800,000 (Direct Cost: ¥2,800,000)
|
Keywords | AGING / GENE EXPRESSION / PROSTACYCLIN / PGI2 / NO / COX / PGI SYNTHASE / PGI RECEPTOR / Nitric Oxide / nitric oxide / prostacyclin / aging / angiotensinII / coronary artery / tyrosine kinase / MAPK / 心臓 |
Research Abstract |
We demonstrated that several vasoconstricting peptides such as angiotensin II (AII) and endothelin-1 (ET-1) increased the production of nitric oxide (NO) and prostacyclin (PGI_2) in the rat hearts. Aging modulated the endothelial function to change the production of NO and PGI_2. It is implicated that PGI_2 plays an important role in the pathogenesis of hypertension, atherosclerosis and thrombosis due to its vasodilating and anti-platelet effect. We examined the age-related changes in the expression of enzymes responsible for the synthesis of PGI_2 and of PGI_2 receptors to reveal the mechanism of regulation of PGI_2 production. Aorta and hearts were isolated from 3-, and 27-months old Fischer 344 rats. Hearts were perfused with constant pressure (75 cmH_2O) at 37℃. Changes in the coronary flow were measured with a flow meter. 6-keto-PGF_1a in the coronary effluent was measured with EIA.Changes in the expression of PGI_2 receptors, PGI synthase and cyclooxygenase-1 (COX-1) were quantified by real-time PCR and Western blot analysis. Release of PGI_2 into the effluent was greater in the aged rat than young rat. There was no age-related difference in the amount of PGI_2 receptor. Expression of COX-1 and PGI synthase was increased in the aged rat. These increases in COX-1 and PGI synthase may be responsible for the increased production of PGI_2 in the aged rat coronary artery.
|