TC-FPR 43 is an agonist of formyl peptide receptor 1 (FPR1) and FPR2, which was previously known as formyl peptide receptor-like 1 (FPRL1).1,2 TC-FPR 43 induces calcium flux in CHO cells expressing human FPR2, Gα15, and aequorin (EC50 = 0.044 ?M) and in CHO-K1 cells expressing either human FPR1, human FPR2, mouse Fpr1, or mouse Fpr2, Gα16, and aequorin in a concentration-dependent manner.2 TC-FPR 43 inhibits migration of polymorphonuclear (PMN) neutrophils induced by fMLP or IL-8 with IC50 values of 0.64 and 0.24 ?M, respectively.1 It also reduces ear swelling induced by prostaglandin E2 and leukotriene B4 in mice when administered at a dose of 50 mg/kg.
1.Bürli, R.W., Xu, H., Zou, X., et al.Potent hFPRL1 (ALXR) agonists as potential anti-inflammatory agentsBioorg. Med. Chem. Lett.16(14)3713-3718(2006) 2.Sogawa, Y., Shimizugawa, A., Ohyama, T., et al.The pyrazolone originally reported to be a formyl peptide receptor (FPR) 2/ALX-selective agonist is instead an FPR1 and FPR2/ALX dual agonistJ. Pharmacol. Sci.111(3)317-321(2009)