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Polyphenol (-)-Epigallocatechin Gallate during Ischemia Limits Infarct Size Via Mitochondrial K(ATP) Channel Activation in Isolated Rat Hearts
Polyphenol (-)-epigallocatechin gallate (EGCG), the most abundant catechin of green tea, appears to attenuate myocardial ischemia/reperfusion injury. We investigated the involvement of ATP-sensitive potassium (K(ATP)) channels in EGCG-induced cardioprotection. Isolated rat hearts were subjected to 3...
Autores principales: | , , , , , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Korean Academy of Medical Sciences
2010
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2826741/ https://www.ncbi.nlm.nih.gov/pubmed/20191036 http://dx.doi.org/10.3346/jkms.2010.25.3.380 |
Sumario: | Polyphenol (-)-epigallocatechin gallate (EGCG), the most abundant catechin of green tea, appears to attenuate myocardial ischemia/reperfusion injury. We investigated the involvement of ATP-sensitive potassium (K(ATP)) channels in EGCG-induced cardioprotection. Isolated rat hearts were subjected to 30 min of regional ischemia and 2 hr of reperfusion. EGCG was perfused for 40 min, from 10 min before to the end of index ischemia. A nonselective K(ATP) channel blocker glibenclamide (GLI) and a selective mitochondrial K(ATP) (mK(ATP)) channel blocker 5-hydroxydecanoate (HD) were perfused in EGCG-treated hearts. There were no differences in coronary flow and cardiodynamics including heart rate, left ventricular developed pressure, rate-pressure product, +dP/dt(max), and -dP/dt(min) throughout the experiments among groups. EGCG-treatment significantly reduced myocardial infarction (14.5±2.5% in EGCG 1 µM and 4.0±1.7% in EGCG 10 µM, P<0.001 vs. control 27.2±1.4%). This anti-infarct effect was totally abrogated by 10 µM GLI (24.6±1.5%, P<0.001 vs. EGCG). Similarly, 100 µM HD also aborted the anti-infarct effect of EGCG (24.1±1.2%, P<0.001 vs. EGCG ). These data support a role for the K(ATP) channels in EGCG-induced cardioprotection. The mK(ATP) channels play a crucial role in the cardioprotection by EGCG. |
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