Anti-stunning and anti-infarct effects of adenosine-enhanced ischemic preconditioning

• Published in: Circulation (New York, N.Y.) N.Y.), 2000-11, Vol.102 (19), p.326-331
• Main Authors: TOYODA, Yoshiya, DI GREGORIO, Vincenzo, PARKER, Robert A, LEVITSKY, Sidney, MCCULLY, James D
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cardiology. Vascular system; Coronary heart disease; Heart; Medical sciences
• ISSN: 0009-7322; 1524-4539

BACKGROUND: Adenosine-enhanced ischemic preconditioning (APC) extends the protection afforded by ischemic preconditioning (IPC) by both significantly decreasing infarct size and significantly enhancing post-ischemic functional recovery. In this study, the anti-infarct effects and the anti-stunning effects of APC in contributing to enhanced post-ischemic functional recovery were determined and compared with IPC. METHODS AND RESULTS: Sheep (n=96) were subjected to 15, 30, 45, or 60 minutes of regional ischemia and 120 minutes of reperfusion. IPC hearts received 5 minutes of regional ischemia and 5 minutes of reperfusion before ischemia/reperfusion. APC hearts received a bolus injection of adenosine coincident with IPC. Adenosine hearts (ADO) received a bolus injection of adenosine before ischemia/reperfusion. Regional ischemia (RI) hearts received no pretreatment. Infarct size/area at risk was determined by tetrazolium staining. Regional myocardial function was determined by sonomicrometry. Segment shortening after 15 minutes of ischemia in which no infarct was incurred was 32. 1+/-10.6% in RI, 70.6+/-8.5% in IPC, and 77.4+/-6.0% in APC hearts. Segment shortening after 30 minutes of ischemia was 60.7+/-6.3% in APC hearts (P: