title: Relationships between IGF-I, cortisol, and osteocalcin in peripheral plasma of growing pigs.
abstract: Osteocalcin is a bone specific protein which is secreted by mature osteoblasts and is measurable in peripheral blood plasma. In growing female pigs (n = 6) osteocalcin was measured in daily blood samples between an age of 125 to 238 days and the values were compared to IGF-I and cortisol. Mean concentrations of osteocalcin were 158 +/- 2.7 ng/ml and the concentrations were significantly correlated to those of IGF-I (r = 0.12 p < or = 0.01 n = 581) and cortisol (r = 0.13 p < or = 0.01 n = 503). Both hormones and less pronounced osteocalcin revealed a rhythm-like pattern with a period of 10-14 days. In addition, rhythm-like variations with a period of about 5 weeks are visible. The highest correlation was found between IGF-I and cortisol both within the animals (r = 0.28, n = 508, p < or = 0.001) and between the individuals (r = 0.94, n = 6, p < or = 0.01). Thus a dialog between IGF-I and cortisol may be assumed. A possible physiological role is discussed.
authors.affiliation: Fachgebiet Tierhaltung und Leistungsphysiologie 470, Universität Hohenheim, Stuttgart, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Claus
authors.forename: U
authors.initials: U
authors.lastname: Weiler
mesh_terms: D000367:Age Factors; D000818:Animals; D002408:Catheters, Indwelling; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000378:metabolism*; D007601:Jugular Veins / Q000601:surgery; D015675:Osteocalcin / Q000097:blood / Q000378:metabolism*; D010507:Periodicity; D011863:Radioimmunoassay; D013552:Swine
chemical_list: D015675:Osteocalcin; D007334:Insulin-Like Growth Factor I; D006854:Hydrocortisone