Abstract: Aim To observe the effects of aspirin in combination with captopril (Cap)on hemodynamics in anesthetized open chest dog s.Methods Tension time index(TTI), left ventricular work index(LVWI), mean arterial pressure (MAP), and total peripheral vascular resistance(T PV R), femoral artery blood f low(FBF), ventricular systolic pressure(LVSP), maximum of its first derivative(+dp/dt_max), left ventricular end diastolic pressure (LVEDP)and heart rate were recorded on polygraph and electromagnetic flower separately when aspirin was administered alone or in combination with captopril.Results The result showed that Asp 5, 10 mg ·kg^-1 had no marked effect on indices of hemodynamics.Cap 0.5mg·kg^-1 iv had no significant effect on LVSP, +dp/dt_max, LVEDP, HR and did not obviously increase cardiac index (CI), but distinctively decreased T TI, LVWI, MAP, TPVR, and significantly increased FBF.The effect of Asp in combination with Cap was similar to that of Cap alone.Conclusion The improvement of cardio vascular function caused by Cap is not changed in the presence of Asp.

Key words: aspirin, captopril, hemodynamics, combination drug therapy