A Study of Parathyroid Hormone Secretion Patterns on Bone Density in Hibernating Black Bears (Ursus americanus)
Loading...
Date
2020
Authors
Eggling, Ali
Kaplow, Sera
Journal Title
Journal ISSN
Volume Title
Publisher
University of Oregon
Abstract
Black Bears (Ursus americanus) have the unique ability to preserve bone structure and strength over the course of hibernation. In other hibernating mammals, decreased load on the skeleton causes a loss of bone density. Parathyroid hormone (PTH) is a regulatory hormone secreted by the parathyroid gland. PTH has been identified as an important regulator in bone metabolism, controlling the coupling of osteoblast and osteoclast production while also regulating blood calcium levels. Abnormal secretion of this hormone is linked to osteoporosis and Paget’s disease, both of which cause a weakening in bone density. Theoretical modeling of PTH secretion cycling suggests that this hormone allows bears to maintain bone strength during hibernation. Our objective is to identify PTH secretion cycles and analyze their correlation with predicted optimal interval release. We predict that Ursus americanus optimize PTH release cycles by closely adhering to a theorized six hour secretion cycle during hibernation. Additionally, we believe that their PTH secretion cycle during hibernation differs from non-hibernating months of the year. We intend to test this by collecting blood samples from hibernating and non-hibernating populations of American black bears and measuring their serum PTH levels over both a daily period and throughout hibernation. This research is closely linked to medical research surrounding disuse osteoporosis, as well as environmental research concerned with identifying a baseline for the biological function of these bears moving into climate driven environmental pressures.
Description
Project files are comprised of 1 page pdf and presentation recording in mp4 format.
Keywords
Bear, Bone, Parathyroid Hormone, Conservation, Osteoporosis