抗高血压活性肽GAP-B的结构及生理功能

Primary Structure and Physiological Activities of New Antihypertensive Dipeptide GAP-B from Casein

本文研究新型乳酪蛋白源抗高血压活性肽GAP-B的分子量与一级结构,并检测其对体内外降血压效果。研究过程采用高效液相与质谱联用、基质辅助激光解吸离子化-飞行时间串联质谱和N端蛋白质序列检测仪等实验方法检测活性肽GAP-B的分子量与氨基酸序列;检测了活性肽产物GAP-B对血管紧张素转化酶(ACE)的抑制活性,并用活性肽GAP-B灌胃自发性高血压大鼠(spontaneously hypertensive rats,SHR)和SD大鼠,观察对SHR和SD大鼠血压的影响。结果显示:抗高血压活性肽GAP-B分子量为M1,氨基酸序列为A1-A2;GAP-B在体外对ACE有很强的抑制活性,抑制率为84.4%;GAP-B对SHR有显著的降血压作用,而对血压正常的SD大鼠的血压没有影响。

Molecular wight and primary structure of new antihypertensive dipeptide GAP-B from casein and its hypertensive effect in vitro-vivo were investigated in this paper. Molecular wight and amino acid sequence of GAP-B were determined by LC-ESi-MS, MALDI-TOP-TOP-MS and N-end protein sequenator. ACE inhibitory activity and antihypertensive activity of GAP-B were measured. The resuh of amino acids analysis showed that the molecule weight and the sequence of GAP-B were respectively M1 and A1-A2. ACE inhibitory activity and antihypertensive activity of dipeptide GAP-B were measured. The results showed that dipeptide GAP-B （50 μg·mL^-1） had significant inhibitory activity against ACE （the rate of inhibitory 84.4%）, the concentration （the dosages of 5 mg·kg^-1 of body weight every day） of antihypertensive dipeptide had remarkable antihypertension on SHR, but it was no use for SD rats.