Calcitonin, a 32 amino acid polypeptide, is involved in the regulation of calcium and phosphorous metabolism often antagonistic to parathyroid hormone (PTH). [Des-Tyr22]-Calcitonin salmon (Des-Tyr22-sCT) is an analogue of calcitonin with decreased in vitro adenylate cyclase activation activity and inhibitory activity for prolactin release from isolated rat pituitary cells.