Calcitonin is a 32-amino acid peptide hormone that lowers blood calcium levels and inhibits bone resorption.1,2 The amino acid sequence of eel calcitonin varies from salmon and human calcitonin at 3 and 16 positions, respectively.3 Calcitonin (eel) binds to calcitonin receptor 2 (CTR2) with higher affinity than human, porcine, or rat calcitonin (Kis = 0.01, 2.95, 0.44, and 5.89 nM, respectively, in radioligand binding assays). It inhibits gastric emptying in conscious dogs more potently than human calcitonin when administered at a dose of 10 ?g/kg.3,4 Calcitonin (eel) increases the paw withdrawal threshold in a mouse model of carrageenan-induced inflammation when administered at a dose of 0.2 ?g/paw.5
1.Foster, G.V.Calcitonin. A review of experimental and clinical investigationsPostgrad. Med. J.44(511)411-422(1968) 2.Chesnut, C.H., III, Azria, M., Silverman, S., et al.Salmon calcitonin: A review of current and future therapeutic indicationsOsteoporos. Int.19(4)479-491(2008) 3.Chen, W.-J., Armour, S., Way, J., et al.Expression cloning and receptor pharmacology of human calcitonin receptors from MCF-7 cells and their relationship to amylin receptorsMol. Pharmacol.52(6)1164-1175(1997) 4.Nakamura, H., Asano, T., and Takeda, K.Gastrointestinal motor inhibition by exogenous human, salmon, and eel calcitonin in conscious dogsCan. J. Physiol. Pharmacol.73(1)43-49(1995) 5.Guidobono, F., Netti, C., Villani, P., et al.Antinociceptive activity of eel calcitonin, injected into the inflamed paw in ratsNeuropharmacology30(12A)1275-1278(1991)