Project/Area Number |
11671322
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Thoracic surgery
|
Research Institution | Kobe University |
Principal Investigator |
TAKURO Tsukube Kobe University Hospital, Department of Surgery II, Assistant Professor, 医学部・附属病院, 助手 (50304100)
|
Co-Investigator(Kenkyū-buntansha) |
安宅 啓二 神戸大学, 医学部, 講師 (20252760)
|
Project Period (FY) |
1999 – 2000
|
Project Status |
Completed (Fiscal Year 2000)
|
Budget Amount *help |
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 2000: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1999: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | myocardial protection / ischemia-reperfusion injury / myocyte / apoptosis / aging / hyperpolarization / カルシュニューリン / 過分極型心筋保護液 |
Research Abstract |
Effect of Hyperpolarized cardioplegic solution on the ischemia-reperfusion injury of the senescent myocardium. Matured rabbit heart was excised and perfused under Langendorff apparatus with modified Krebs-Henseleit buffer solution and adenosine cardioplegia (with 10mM magnesium sulfate) was infused prior to the ischemia. Functional recovery (% recovery of the left ventricular developed pressure) after 30 minutes ischemia demonstrated 14±3% greater recovery than control. In aged rabbit heart, global ischemia without treatment showed 60±5% recovery of LV developed pressure and improved in 22±3% with adenosine cardioplegia. After 45 minutes of ischemia followed by 240 minutes of reperfusion under cardiopulmonary bypass, adenosine cardioplegia improved LV pressure (25±5%) as compared to global ischemia without treatment. TUNEL stainin positive myocyte was significantly decreased in adenosine cardioplegia (23±5%) as compared to control ischemia (32±7%). These findings proved hyperpolarized cardioplegia ameliorated ischemia-reperfusion injury on both mature and aged myocardium. Effect of calcineurin inhibitors on myocardial apoptosis To prevent myocardial apoptosis, calciueurin inhibitor (FK-506) was applied and functional recovery and TUNEL staining were evaluated in both mature and aged rabbit hearts. In the mature hearts, % recovery of LV developed pressure was greater in FK-506 pretreated group (20±4%) than in ischemia without treatment. TUNEL staining positive myocytes were significantly decreased in FK-506 group. In the aged hearts, FK-506 significantly improved functional recovery (17±3%) and decreased TUNEL staining positive myocytes (32±7%) as compared to those in ischemia without treatment. These studies proved that myocardial apoptosis was key disease process of ischemia-reperfusion injury and hyperpolarized cardioplegia ameliorated these insults on aged myocardium.
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