Activation of Mitochondrial ATP-Sensitive Potassium Channel Contributes to Protective Effect in Prolonged Myocardial Preservation

Wei Guo; Nan Chen; Yingying Chen; Qiang Xia; Yueliang Shen

doi:10.1109/IEMBS.2005.1615345

Activation of Mitochondrial ATP-Sensitive Potassium Channel Contributes to Protective Effect in Prolonged Myocardial Preservation

Conf Proc IEEE Eng Med Biol Soc. 2005:2005:4027-30. doi: 10.1109/IEMBS.2005.1615345.

Authors

Wei Guo¹, Nan Chen, Yingying Chen, Qiang Xia, Yueliang Shen

Affiliation

¹ Dept. of Phys., Zhejiang Univ. Sch. of Med., Hangzhou.

PMID: 17281115
DOI: 10.1109/IEMBS.2005.1615345

Abstract

To find a better strategy for effective donor organ preservation, here we used a model of long-term hypothermia preservation of rat hearts to investigate the cardioprotective effects of diazoxide, a selective opener of mitochondrial ATP-sensitive potassium channel (mitoK_ATP). Cardiac function was impaired by 8-hour ischemic preservation following 30 minutes of reperfusion. Treatment with diazoxide significantly attenuated the decline of myocardial contractility, and decreased the lactate dehydrogenase leakage and myocardial edema. Diazoxide also prevented the loss of activity of mitochondrial superoxide dismutases and sarcolemmal Na⁺/K⁺ ATPase during ischemia or reperfusion period, respectively. These effects of diazoxide could be abolished by a selective mitoK_ATp blocker 5-hydroxydecanoate. The results suggest that diazoxide, as a supplementation in cardioplegic solution, could enhance myocardial protection by opening mitoK_ATp channel, and better maintenance of mitochondrial anti-oxidative enzyme.