Angiotensin I converting enzyme(ACE)inhibitory activity and antihypertensive effects of rice peptides

In this paper,the antihypertension effect of rice peptide(RP)was studied.With spontaneously hypertensive rats(SHR)and Wistar Kyoto(WKY)as the research objects,RP disposable gastric and long-term gastric irrigation experiments were carried out and systolic blood pressure(SBP)was measured.At the end of the long-term gastric irrigation experiment,the content of nitric oxide(NO),angiotensin-converting enzyme(ACE),angiotensin II(Ang II)and renin in the plasma and the activity of ACE were determined.The results showed that RP could reduce systolic pressure of SHR and had time-dose dependence while high-dose RP signifi cantly reduced systolic pressure by 24.6 and 17.2 mm Hg,respectively after a single and long-term gastric irrigation test.RP also could inhibit the activity of ACE and increase the release of NO.These results suggested that the decompression mechanism of RP is likely to be related to the regulation of the renin-angiotensin system(RAS)and NO.

Interaction mechanism of egg white-derived ACE inhibitory peptide TNGIIR with ACE and its effect on the expression of ACE and AT1 receptor

The egg white-derived hexapeptide TNGIIR inhibits angiotensin-converting enzyme(ACE)activity in vitro.In this work,molecular docking revealed that TNGIIR established hydrogen bonds with the S1(Ala 354),S2(Gln 281,His 513,Tyr 520 and Lys 511)and S1(Glu 162)pockets of ACE.In addition,the potential antihypertensive effect of the oral administration of TNGIIR in spontaneously hypertensive rats(SHR)was investigated,as was the effect of this peptide on the mRNA expression of ACE and angiotensin type 1(AT1)and type 2(AT2)receptors in renal tissue.The oral administration of TNGIIR(2,10 and 50 mg/kg)for up to four weeks did not reduce the blood pressure of SHR,in contrast to captopril(10 mg/kg,orally),but attenuated the mRNA expression of ACE and AT1 receptor(as did captopril).In contrast,both TNGIIR and captopril enhanced the expression of AT2 receptor mRNA.There was no change in the circulating concentration of angiotensin I,but a slight decrease(about 10%)was seen in the concentration of circulating angiotensin II with TNGIIR and captopril.

Clinical Significance of Evaluating Antihyperten-sive Effect with Arterial Compliance

Objective To evaluate the clinical significance of antihypertensive effect with arterial compliance. Methods In males, 72 cases were control group, 35 cases were EH-controlled, and 35 cases were EH-uncontrolled groups. Blood pressure and arterial compliance (Cl and C2) were detected by HDI DO-2020. Results In the EH-uncontrolled group,the values of systolic blood pressure ( SBP ) , diastolic blood pressure (DBF) , mean arterial pressure (MAP ) , and pulse pressure (PP) were significantly higher than those of the control and the EH-controlled groups (P<0. 01) , however,there was no difference between the control and the EH-controlled groups. In the EH-uncon-trolled group,the values of Cl and C2 were lower than those of both the control and the EH-controlled groups (P<0. 01) ,again,wtih no difference between the control and the EH-controlled groups. Conclusion Arterial compliance (Cl and C2) measurements may serve as a sensitive indicator of evaluating antihypertensive effect.