Development of cardioplegia for newborn cardiac surgery.

2005 Fiscal Year Final Research Report Summary

• Project/Area Number: 15390408
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Thoracic surgery
• Research Institution: Nagoya University
• Principal Investigator: UEDA Yuuichi Nagoya University, Graduate School of Medicine, Professor, 大学院・医学系研究科, 教授 (80314011)
• Co-Investigator(Kenkyū-buntansha): AKITA Toshiaki Nagoya University, University Hospital, Assistant Professor, 医学部附属病院, 講師 (30167837) ; USUI Akihiko Nagoya University, Graduate School of Medicine, Associate Professor, 大学院・医学系研究科, 助教授 (30283443) ; KODAMA Itsuo Nagoya University, Department of Environmental Medicine, Professor, 環境医学研究所, 教授 (30124720) ; YASUI Kenji Nagoya University, Department of Environmental Medicine, Professor, 環境医学研究所, 教授 (70283471)
• Project Period (FY): 2003 – 2005
• Keywords: Glycolysis / deoxyglucose / glibenclamide / immature myocardium / cardioplegia / I_<KATP> channel

Research Abstract

To elucidate the role of anaerobic glycolysis durnig ischemia for the genesis of subsequent
reperfusion injury in neonatal hearts, we investigated the effects of glucose and deoxyglucose(DG) on isolated neborn(2-5 days) rabbit hearts perfused in vitro. Following cardiac arrest induced by St. Thomas' Hospital cardioplegic solution(ST), the hearts were subjected to hypothermic ischemia for 180 min. Glucose(5mM) or DG(5mM) was added to ST. Percentage recovery of left ventricular developed pressure(LVDP) after 30 min reperfusion, lactate/pyruvate ratio(L/P) in the coronary effluent during the first minute of reperfusion and CK leakage were as follows(^*p<0.05 vs ST, ANOVA) :
%rec LVDP L/P ratio CK leakage
ST 72.7+3.3 23.3+1.2 41.5+13.0
ST+glucose 58.9+3.9^* 36.9+4.4^* 40.0+5.3
ST+DG 96.3+1.4^* 17.3+3.8^* 18.9+4.5^*
Addition of glucose resulted in a decrease in % rec of LVDP and an increase in L/P, an index of redox state. DG application caused a significant increase in % rec of LVDP and a decrease in L/P as well as in CK leakage. These results suggested that anaerobic glycolysis during in neonatal hearts during ischemia mya set a stage for larger Ca overload with Na+/H+ and Na+/Ca2+ exchange, leading to greater myocardioal injury. potential usefulness of DG in cardioplegia was proposed.