IMMUNOREACTIVE HUMAN CALCITONIN-LIKE MOLECULE IN THE NERVOUS SYSTEMS OF PROTOCHORDATES AND A CYCLOSTOME, MYXINE

Abstract
A molecule very closely resembling human calcitonin immunologically and chromatographically was extracted from the nervous systems of several protochordates and a cyclostome, Myxine. The presence of human calcitonin-like molecules in the nervous systems of primitive chordates suggests that they have some function in the nervous system of these species and that the bone-regulating function of the calcitonins may have arisen much later in the vertebrates.