The Effect of Continuous Infusion of Human Parathyroid Hormone on Bone Architecture in Female Mice

This research sought to create an animal model of secondary hyperparathyroidism through continuous infusion of parathyroid hormone (PTH) in adult female mice, and to subsequently study the catabolic effects of PTH. Osmotic pumps were implanted subcutaneously and infused either vehicle, 40 pg/kg/day of PTH or 80 pg/kg/day of PTH for either 2 week or 4 week duration. Total body bone mineral density (BMD) and bone mineral content (BMC), trabecular and cortical bone microarchitecture, and serum calcium levels were measured. There were no significant differences in BMD or BMC in either study in mice infused with either dosage, nor were there significant differences in femoral cortical bone microarchitecture. Trabecular bone in the distal femur as well as the L5 vertebrae was also largely preserved. This data indicate that short term infusion of PTH in normal mice does not mimic clinical characteristics and therefore may not be an appropriate model of secondary hyperparathyroidism and the catabolic effects of PTH. Thesis Supervisor: Myron Spector Title: Senior Lecturer of Harvard-MIT Division of Health Sciences and Technology