Effects Of Tea Polyphenols On Cardiac Function In Experimental Animals And Preliminary Explore Of Probable Mechanism

the purpose of the work was to observe the effects of tea polyphenols (TP) on the hearts in vivo and in vitro in rabbits and the isolated hearts of the frogs, and to explore its probable mechanism by myocardial contractility. To observe the effects of TP with concentration of 30mg/kg on Cardiac function in rabbit's heart in vivo by means of left ventricle cardiac catheter techniques and the hemodyramics method: The results showed that dp/dtmax , -dp/dtmax , HR and LVSP were increased after intravenous injection TP (P<0.05), While the LVDEP was not changed(P>0.05). At the same time, the SP, MP and DP were obviously decreased above 16.78%(P<0.01), it indicated that TP could significantly enhance the myocardial contractility and the pumping fuction, and dilate the peripheral blood vessels. In the hearts of the frogs, TP played double effects in cardiac contractility, it also showed dose-dependence positive inotropic action after used TP with concentration of 0.5～50μg/L, but the positive inotropic action would decend even the heart stop beating when the concentration increased. The positive inotropic action have nothing to do with the...