Proteinase-activated receptor-4:: Evaluation of tethered ligand-derived peptides as probes for receptor function and as inflammatory agonists in vivo
Proteinase-activated receptor-4:: Evaluation of tethered ligand-derived peptides as probes for receptor function and as inflammatory agonists in vivo
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DOI：
10.1038/sj.bjp.0705946
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发表时间：
2004-10-01
影响因子：
7.3
通讯作者：
Vergnolle, N
中科院分区：
文献类型：
--
作者：
Hollenberg, MD;Saifeddine, M;Vergnolle, N
1我们评估了一些基于人、大鼠和小鼠蛋白水解酶激活受体-4(PAR(4))的连接配体序列作为受体激活探针或拮抗剂的能力，用于体外生物测定和体内炎症模型。2在依赖PAR(4)的大鼠血小板聚集实验中，活性序列的相对效力(AYPGKF-NH2>；GYPGKF-NH2>；GYPGFK-NH2>；3在聚集实验中，反向或部分逆序多肽(VQGPYG-NH2、YAPGKF-NH2和FKGPYA-NH2)是无效的，而反式-肉桂酰基(TC)-YPGKF-NH2、TC-APGKF-NH2和N-Palmitoyl-SGRYGHALR-NH2(多肽P4PAL-10)是拮抗剂。4然而，在内皮依赖性NO介导的大鼠主动脉(RA)松弛实验和胃肌纵向收缩(LM)实验中，这些拮抗剂是激动剂5我们得出结论，PAR(4)衍生的栓系配基多肽激动剂可以作用于PAR(4)以外的受体，并且需要明智地选择配体来探测生物测定系统中的PAR(4)功能，特别是对于活体模型。6通过从这些多肽中选择最可靠地反映PAR(4)激活的那些(AYPGKF-NH2作为标准激动剂；YAPGKF-NH2作为PAR(4)失活标准)，我们能够在大鼠足肿胀模型中建立PAR(4)激活肽通过非神经源性机制起作用的炎症作用。
1 We evaluated the ability of a number of peptides based on the tethered ligand sequences of human, rat and murine proteinase-activated receptor-4 (PAR(4)), to serve as receptor-activating probes or antagonists for bioassays carried out in vitro and for in vivo models of inflammation.2 In a rat PAR(4)-dependent platelet aggregation assay, the relative potencies of the active sequences (AYPGKF-NH2>GYPGKF- NH2>GYPGFK- NH2>GFPGKP-NH2) were consistent with an activation of PAR(4).3 In the aggregation assay, the reverse or partial reverse-sequence peptides ( VQGPYG-NH2, YAPGKF-NH2 and FKGPYA-NH2) were inactive, while trans-cinnamoyl (Tc)- YPGKF-NH2, Tc-APGKF- NH2 and N-palmitoyl-SGRRYGHALR-NH2 (pepducin P4pal-10) were antagonists.4 However, in an endothelium-dependent NO-mediated rat aorta ( RA) relaxation assay and in a gastric longitudinal muscle (LM) contraction assay, these antagonist peptides were agonists as were most other peptides, with distinct orders of potencies that differed for both the RA and LM assays and from the platelet assay.5 We conclude that PAR(4)-derived tethered ligand peptide agonists can act at receptors other than PAR(4) and that a judicious choice of ligands is required to probe for PAR(4) function in bioassay systems and in particular for in vivo models.6 By selecting from these peptides the ones most reliably reflecting PAR(4) activation (AYPGKF-NH2 as a standard agonist; YAPGKF-NH2 as a PAR(4)-inactive standard), we were able to establish an inflammatory role for the PAR(4)-activating peptides acting via a non-neurogenic mechanism in a rat paw oedema model.