2013 Fiscal Year Final Research Report

The search for sterss-induced conditioning: effects of acute hypercapnia

Research Project

Project/Area Number	23592257
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Anesthesiology/Resuscitation studies
Research Institution	Nagasaki University
Principal Investigator	HARA Tetsuya 長崎大学, 医歯(薬)学総合研究科, 教授 (50304952)
Project Period (FY)	2011 – 2013
Keywords	心筋虚血 / コンディショニング / 高炭酸ガス血症 / 気絶心筋
Research Abstract	We studied the cardioprotective effect of acute hypercapnia before ischemia or during reperfusion (pre- or post-conditioning) in swine stunned myocardium. Hypercapnia was induced by hypoventilation of PaCO2 70 mmHg for 30 minutes. Stunning was produced by 12-min ischemia and 90-min reperfusion. Myocardial contractility was evaluated with segment shortening. Data were analyzed with Mann-Whitney U test. p<0.05 was considered statistically significant. PaCO2 and coronary blood flow during hypercapnia were significantly higher than those in control swine. There was no significant recovery of stunning. Interleukin after reperfusion were slightly attenuated in pre-conditioned swine. KATP channels were not activated during hypercapnia. Acute hypercapnia could not enhance recovery of stunned myocardium. Attenuation of the preconditioning stimuli by the increase of coronary blood flow would be considered as the result, and therefore enough conditioning stimuli would not be obtained.