Relative Importance of Parathyroid Hormone and Thyrocalcitonin in Calcium Homeostasis

Abstract

ALTHOUGH it has long been recognized that the serum calcium is maintained within rigid physiologic limits, it is only in the past decade that the hormonal factors involved in this regulation have been defined in biochemical terms and that detailed investigation of their mode of action has been initiated. Developments during this period have included the following: purification of bovine parathyroid hormone (PTH) and partial characterization of the molecular features essential for its biologic activity¹; examination of a variety of in vivo and in vitro models to define the mechanism of action of the hormone²; direct measurement of . . .