Yamada Akio, Sakurai Takuma, Ochi Daisuke, Mitsuyama Eri, Yamauchi Koji, Abe Fumiaki
Morinaga Milk Industry Co., Ltd, Functional Food Research Department, Food Science & Technology Institute, 1-83, 5-Chome, Higashihara, Zama-City, Kanagawa-Pref. 252-8583, Japan.
Morinaga Milk Industry Co., Ltd, Functional Food Research Department, Food Science & Technology Institute, 1-83, 5-Chome, Higashihara, Zama-City, Kanagawa-Pref. 252-8583, Japan.
Food Chem. 2015 Apr 1;172:441-6. doi: 10.1016/j.foodchem.2014.09.098. Epub 2014 Sep 28.
The antihypertensive effect of the bovine casein-derived peptide Met-Lys-Pro (MKP) was examined in vitro and in vivo. MKP showed angiotensin I-converting enzyme (ACE)-inhibitory activity in vitro (IC50 = 0.43 μM). An in vivo kinetics study using radiolabeled Met-[1-(14)C]Lys-Pro ((14)C-MKP) showed that orally administered (14)C-MKP to spontaneously hypertensive rats (SHRs) was absorbed and moved into the plasma. In vitro vasoconstriction of thoracic aorta preparations, which was induced by adding angiotensin I, was reduced by prior exposure of MKP. A single oral dose of MKP lowered systolic blood pressure (SBP) of SHRs, and repeated oral administration of MKP for 28 days significantly lowered SBP of SHRs. The results obtained in the present study suggest that orally administrated MKP can be absorbed into the plasma and its ACE-inhibitory activity may contribute to induce the antihypertensive effect in vivo.
对源自牛乳酪蛋白的肽Met-Lys-Pro（MKP）的降压作用进行了体外和体内研究。MKP在体外显示出血管紧张素I转换酶（ACE）抑制活性（IC50 = 0.43μM）。使用放射性标记的Met-[1-(14)C]Lys-Pro（(14)C-MKP）进行的体内动力学研究表明，给自发性高血压大鼠（SHR）口服(14)C-MKP后，其被吸收并进入血浆。预先用MKP处理可减轻因添加血管紧张素I诱导的胸主动脉制剂的体外血管收缩。单次口服剂量的MKP可降低SHR的收缩压（SBP），连续28天重复口服MKP可显著降低SHR的SBP。本研究获得的结果表明，口服的MKP可被吸收进入血浆，其ACE抑制活性可能有助于在体内产生降压作用。
