Abstract: Aim The effects of tea polyphenols (TP) on phosphoinositides metablism in rats with acute ischemic myocardium were studied. Methods The model of acut myocardial ischemia in rats was prepared by ligating anterior decending branch of left coronary artery. Results The functio1l of the phosphoinositide signal system was enhanced 10 min after acute myocardial is-chemia. Both of the levels of phosphotidylinositol-4,5-biphosphate(PIP₂) and inositol -1,4,5-triphosphate (IP₃)were higher than those in the non - ischemic control group(P<0.01).The rise of the levels of PIP₂ and IP₃ caused by myocardial ischemia were remarkedly in-hibited by the TP and a dose - effect relalionship was observed (P<0.01). Conclusion The results showed that the protection of TP was relation to its inhibiting the function of phosphoinositides metablism in acute ischemic myocardium.

Key words: Myocardial ischemia, Phosphotidylinositol-4, 5-biphosphate, Inositol-1,4,5-triphosphate, Tea polyphenols