PRIMARY STRUCTURE AND BIOACTIVITY OF BULLFROG CALCITONIN

Calcitonin was isolated from the bullfrog, Rana catesbeiana, and the f irst amino acid sequence of an amphibian calcitonin was determined to be r-Tyr-Pro-Arg-Thr-Asn-Val-Gly-Ala-Gly-Thr-Pro-NH2. Some portions of this sequence are specific to bullfrog calcitonin, and other portions are similar both to teleost calcitonins and to mammalian calcitonins. Administration of 5 pmol of bullfrog calcitonin to rats revealed a hy pocalcemic potency similar to that of salmon calcitonin, at least for the first 3 hr. (C) 1997 Academic Press.