AIM To study the pathogenetic roles of heart derived angiotensin Ⅱ (Ang Ⅱ) and norepinephrine (NE) in (stunned myocardium) and cardioprotective effects of calcium antagonist F 3 (1,4 dihydropyridines).METHODS Rabbits were surgically prepared for coronary arterial occlusion and reperfusion. Changes of myocardial renin activity, the content of AngⅡ and NE were observed on the brief postischemic reperfused myocardium in intact rabbits by using RIA. F 3 was used in treatment before ischemia. RESULTS There were significant increase in renin activity and AngⅡ concentrations in stunned myocardium, as compared with those in controls. The NE concentrations of myocardium increased significantly in stunned myocardium ( P< 0 01). Administration of F 3 (3 mg·kg -1 ,Ⅳ) before 15 min in brief ischemia and 15 min reperfusion reduced levels of AngⅡ and NE in the heart dramatically. CONCLUSION The results suggest that heart AngⅡ and NE play important roles in the pathogenesis of brief postischemic reperfused myocardium, F 3 is beneficial to brief postischemic reperfused myocardium.