Abstract 1135: Hydrogen Peroxide Plays a Crucial Role in Coronary Microvascular Vasodilation with Increased Oxidative Stress in Right Ventricles of Pulmonary Hypertensive Rats
| العنوان: | Abstract 1135: Hydrogen Peroxide Plays a Crucial Role in Coronary Microvascular Vasodilation with Increased Oxidative Stress in Right Ventricles of Pulmonary Hypertensive Rats |
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| المؤلفون: | Masahito Kajiya, Yousuke Inai, Taro Morimoto, Tatsuo Iwasaki, Kousuke Endo, Satoshi Mohri, Toyotaka Yada, Keiji Naruse, Tohru Ohe, Fumihiko Kajiya |
| المصدر: | Circulation. 116 |
| بيانات النشر: | Ovid Technologies (Wolters Kluwer Health), 2007. |
| سنة النشر: | 2007 |
| مصطلحات موضوعية: | Physiology (medical), Cardiology and Cardiovascular Medicine |
| الوصف: | Background: Hydrogen peroxide (H 2 O 2 ) is a well recognized candidate for EDHF. The aim of this study was to examine H 2 O 2 -EDHF function in coronary arterial microvessels under conditions of increased oxidative stress in RV of pulmonary hypertension (PH). Methods: Monocrotaline (60 mg/kg SC) was administrated in 5 week-age male Sprague-Dawley rats to induce PH (PH; n=52). Saline was injected in control rats (n=47). After 3 weeks, RV coronary arterioles (CA; 30 –100 μm) and small arteries (CSA; 100 –200 μm) were visualized in vivo using our intravital videomicroscopy. After cyclooxigenase blockade, Acetylcholine (ACh; 2 μg/kg/min IV) induced vasodilation was evaluated under three conditions; ACh alone, N ω nitro-L-arginine methyl ester (L-NAME), L-NAME+catalase. Differences of percentage vasodilation between ACh alone and L-NAME, and between L-NAME and L-NAME+catalase were used as relative indices for the contributions of NO and H 2 O 2 -EDHF, respectively. Malondialdehyde (MDA) in plasma was measured with colormetric assay. Superoxide production in RV was determined by lucigenin-derived chemiluminescence. Results: RV systolic pressure was significantly increased in PH (75±13 vs. 31±3 mmHg; p2 O 2 -EDHF in PH was greatly increased for both CA (from 48% to 60%) and CSA (from 28% to 53%) (both p2 O 2 produciton and contribute to the robust EDHF function. Conclusion: Under conditions of increased oxidative stress in PH, H 2 O 2 -EDHF plays a crucial role against NO dysfunction in RV coronary microcirculation. |
| تدمد: | 1524-4539 0009-7322 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::0955219e8f2d16fc0347c2f4674e9029 https://doi.org/10.1161/circ.116.suppl_16.ii_228-c |
| رقم الأكسشن: | edsair.doi...........0955219e8f2d16fc0347c2f4674e9029 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15244539 00097322 |
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