title: Assessment of the degradation of thyroid hormones in man during bed rest.
abstract: The effect of bed rest on the absolute turnover rates of thyroid hormones, thyroxine (T4) and triiodothyronine (T3), was evaluated in man. Bed rest resulted in physical deconditioning, measured by a decreased rate of maximal oxygen consumption; physical deconditioning was associated with no significant alterations in the metabolic clearance of T4 and T3. Plasma concentrations of these iodothyronines were not changed as a result of bed rest. Absolute hormone turnover rates were similar in control and bed-rest subjects. The data suggest that the degradation of thyroid hormones is not influenced by physical deconditioning or hypodynamia.
mesh_terms: D000293:Adolescent; D000328:Adult; D006801:Humans; D007700:Kinetics; D008297:Male; D010101:Oxygen Consumption; D010809:Physical Fitness; D012146:Rest; D013974:Thyroxine / Q000097:blood / Q000378:metabolism*; D014284:Triiodothyronine / Q000097:blood / Q000378:metabolism*
chemical_list: D014284:Triiodothyronine; D013974:Thyroxine