title: Net fluxes over working thigh of hormones, growth factors and biomarkers of bone metabolism during short lasting dynamic exercise.
abstract: The purpose of this study was to evaluate the responses of hormones, growth factors, and biomarkers involved in bone and muscle metabolism during exercise and in recovery. One leg knee-extension exercise and concomitant sampling from the artery and vein were performed. In 12 healthy individuals (6 men and 6 women; age 21-36 years) blood was drawn from the femoral artery and vein at rest, after 10 minutes warm-up, after 15 minutes work at 61% of peak one leg VO2, and after 5 minutes work at peak one leg VO2, as well as 5, 30, and 60 minutes in recovery. Blood flow in the femoral vein was measured using the thermodilution technique. Arteriovenous differences were measured over working thigh for growth hormone (GH), insulin-like growth factor I (IGF-I), insulin-like growth factor binding protein 3 (IGF BP3), parathyroid hormone (PTH) and bone biomarkers, i.e., the carboxyterminal propeptide of type I procollagen (PICP), the carboxyterminal cross-linked telopeptide of type I collagen (ICTP), osteocalcin, and bone-specific alkaline phosphatase (b-ALP). There was an uptake of GH (3.1 +/- 1.2 mU x min(-1), P < 0.001; mean +/- SE) over thigh during exercise and a release of IGF-I at the end of exercise (60 +/- 36 microg x min(-1); P < 0.01). PICP was also released after the maximal exercise (23 +/- 12 microg x min(-1); P < 0.01) as well as ICTP (0.5 +/- 0.3 microg x min(-1); P < 0.05) and b-ALP (0.2 +/- 0.1 microkat x min(-1); P < 0.05). Osteocalcin, IGF BP3, and PTH revealed no clearcut pattern. In the present study, exercise induces endocrine changes which point to anabolic effects on muscle and bone tissue.
authors.affiliation: Department of Internal Medicine, University Hospital, Uppsala, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Brahm
authors.forename: K
authors.initials: K
authors.lastname: Piehl-Aulin
authors.forename: B
authors.initials: B
authors.lastname: Saltin
authors.forename: S
authors.initials: S
authors.lastname: Ljunghall
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D001842:Bone and Bones / Q000378:metabolism*; D003094:Collagen / Q000097:blood; D024042:Collagen Type I; D015444:Exercise / Q000502:physiology*; D005260:Female; D006133:Growth Substances / Q000097:blood*; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D019344:Lactic Acid / Q000097:blood; D008297:Male; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides / Q000097:blood; D011347:Procollagen / Q000097:blood; D012709:Serum Albumin / Q000378:metabolism; D013848:Thigh
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D006133:Growth Substances; D018972:Insulin-Like Growth Factor Binding Protein 3; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; D012709:Serum Albumin; C052929:collagen type I trimeric cross-linked peptide; C042813:procollagen type I carboxy terminal peptide; D015675:Osteocalcin; D019382:Human Growth Hormone; D019344:Lactic Acid; D007334:Insulin-Like Growth Factor I; D003094:Collagen