Kinetensin is a nonapeptide that has been found in pepsin-treated human plasma.1 It binds to neurotensin receptors in HT-29 cells and mouse brain (Kis = 1,396 and 149.6 nM, respectively, in radioligand binding assays) but does not induce the accumulation of intracellular calcium in HT-29 cells (EC50 = >10,000 nM).2 It induces histamine release in isolated rat peritoneal mast cells with an EC50 value of approximately 10 µM.3 Intradermal administration of kinetensin induces vascular permeability in rats.
1.Mogard, M.H., Kobayashi, R., Chen, C.F., et al.The amino acid sequence of kinetensin, a novel peptide isolated from pepsin-treated human plasma: Homology with human serum albumin, neurotensin and angiotensinBiochem. Biophys. Res. Commun.136(3)983-988(1986) 2.Akunne, H.C., Demattos, S.B., Whetzel, S.Z., et al.Agonist properties of a stable hexapeptide analog of neurotensin, NαMeArg-Lys-Pro-Trp-tLeu-Leu (NT1)Biochem. Pharmacol.49(8)1147-1154(1995) 3.Sydbom, A., Ware, J., and Mogard, M.H.Stimulation of histamine release by the peptide kinetensinAgents Actions27(1-2)68-71(1989)