In order to evaluate the effect of
soy oligopeptides administration on blood pressure, the animal tests and the clinical
test were carried out in this study. The hypertensive rats (SHR, 9 male rats and 21 female) purchased from Beijing Fuwai Hospital) were divided into three groups. The first group was given in a high dose of
soy oligopeptides <1 200 mg/(kg·day)>, the second group was given in a low dose of soy oligopeptides <600 mg/(kg·d)>, and the third group was taken as control fed without soy oligopeptides. All samples had been given by oral
administration. Systolic blood pressure (SBP) was measured by the tail pressure and cardiotachometer.The soy oligopeptides showed potent antihypertensive effect in male SHR rats. The soy oligopeptides showed that Systolic Blood Pressure (SBP) decreased 30 mmHg in male SHR rats (1.2 g /kg of body weight / day)compared the control group from third day after administration. The soy oligopeptides also showed a potent antihypertensive effect in female SHR rats. At seventh day after administration, the antihypertensive effect reached a peak value, which dropped soon afterwards. Meanwhile, the high dose group showed more stable antihypertensive effect than low dose one. However, In the control groups, no changes in SBP occurred during oral administration. In clinical test, according to the method of China Guide of Hypertension, 40 primary hypertensive patients were screened including 25 males and 25 females, which of mean age was 51.66±11.35 years old. After taking the soy oligopeptides for one month, blood pressure and heart rate were determined. ECG was recorded and the related blood indexes were arrayed. Results showed that the Systolic Blood Pressure (SBP) decreased from 142.52 mmHg to 134.38 mmHg (p=0.001), while the Diastolic Blood Pressure (SBP) decreased from 88.98mmHg to 84.57 mmHg (p=0.007). K+、Na+ level in serum increased obviously (p=0.029, p=0.000) , while Ca 2+ and P 5+ didn't show any significant changes. Mg 2+ was lower than before (p=0.000). What are more, other related indexes kept the same level. So we concluded that the soy oligopeptides may decreased the blood pressure of primary hypertensive patients and the mechanism perhaps was related with the inhibition of ACE.