[Effects of antihypertensive factor on cardiac function in spontaneously hypertensive rats].

In this study, we observed the effects of erythrocytic AHF from normotensive human subjects on heart function of stroke prone SHR (SHRsp) in order to investigate the antihypertensive mechanism of AHF. The results showed that AHF significantly decreased the heart rate (HR), left ventricular end systolic pressure (LVESP), and magnitude of +/- LVdP/dtmax, but had no effect on Wistar Kyoto (WKY) rats, indicating that AHF has negative chronotropic and inotropic action on SHRsp hearts. AHF also lowered the contraction amplitude and resting tension in isolated SHRsp hearts, but had no effect on HR and blood flow of the coronary artery, indicating that AHF exerts negative inotropic action on isolated SHRsp hearts. The results suggest that the antihypertensive mechanism of AHF may be related to its ability to decrease cardiac function in hypertensive rats.