C - Michigan Technological University

hibernation. This report brings to light several potential hormonal effectors of reducedbone turnover, but raises new questions. Is it possible to attenuate disuse-induced boneloss by inducing hypometabolic states in osteoblasts and osteoclasts? If so, such amechanism could be applied to protect people who are at risk of disuse induced boneloss (e.g. paralyzed patients, astronauts, patients confined to long-term bed-rest, orsubmariners). Most current studies on the effects of reduced bone turnover on bonemechanical strength and structure suggest that this condition reduces bone strength andBMD; however, these studies tend to take place in young (i.e. rapidly growing) rodents,and there are no known studies on the effects of suppressing bone turnover inconditions of disuse. The hormones brought to light in this study may work together todesensitize bone to mechanical stimulus by inducing hypometabolic states in theosteoblasts and osteoclasts. Studying the effects of these hormones on mechanicallyunloaded bones could yield intriguing results. Therefore, this report has achieved onesmall step in the long-term goal to determine the mechanism through which bearsmaintain bone during hibernation and to develop a treatment for people at risk of disuseosteoporosis.135