绵羊κ-酪蛋白肽可抑制血小板聚集。

Sheep kappa-casein peptides inhibit platelet aggregation.

作者信息

Qian Z Y, Jollès P, Migliore-Samour D, Schoentgen F, Fiat A M

机构信息

Laboratoire des Protéines, CNRS URA 1188, University of Paris V, France.

出版信息

Biochim Biophys Acta. 1995 Jun 9;1244(2-3):411-7. doi: 10.1016/0304-4165(95)00047-f.

DOI:10.1016/0304-4165(95)00047-f

PMID:7599162

Abstract

The C-terminal part (residues 106-171) of sheep kappa-casein, called caseinoglycopeptide (CGP), inhibits thrombin- and collagen-induced platelet aggregation in a dose-dependent manner (mean inhibitory concentration (IC50) 215 microM and 100 microM, respectively). An enzymatic hydrolysate of CGP was fractionated by reverse phase high performance liquid chromatography: three peptides KDQDK (residues 112-116), TAQVTSTEV (residues 163-171) and QVTSTEV (residues 165-171) completely inhibited thrombin-induced platelet aggregation. CGP at a concentration near its IC50 had a very long life when incubated in human or guinea-pig plasma. An ex vivo experiment showed that 17% of CGP was found 60 min after its i.v. bolus injection in guinea-pig. By hydrophobic cluster analysis, human fibrinogen and sheep kappa-casein peptides, inhibitors of platelet aggregation, were compared and we observed similarities for their C-terminal parts and for their short peptides (RGDF and KDQDK).

摘要

绵羊κ-酪蛋白的C末端部分（第106 - 171位氨基酸残基），称为酪蛋白糖肽（CGP），以剂量依赖方式抑制凝血酶和胶原蛋白诱导的血小板聚集（平均抑制浓度（IC50）分别为215微摩尔和100微摩尔）。通过反相高效液相色谱法对CGP的酶解产物进行分离：三种肽KDQDK（第112 - 116位氨基酸残基）、TAQVTSTEV（第163 - 171位氨基酸残基）和QVTSTEV（第165 - 171位氨基酸残基）完全抑制凝血酶诱导的血小板聚集。当在人或豚鼠血浆中孵育时，接近其IC50浓度的CGP具有很长的半衰期。一项体内实验表明，在豚鼠静脉推注CGP 60分钟后，发现17%的CGP仍存在。通过疏水簇分析，比较了人纤维蛋白原和绵羊κ-酪蛋白肽（血小板聚集抑制剂），我们观察到它们的C末端部分以及短肽（RGDF和KDQDK）具有相似性。