title: Effects of cortisol secreted via a 12-h infusion of adrenocorticotropic hormone on mineral homeostasis and bone metabolism in ovariectomized cows.
abstract: To evaluate the effects of endogenously secreted cortisol on mineral homeostasis and bone metabolism in cows, 4 ovariectomized Holstein cows were infused for 12 h with either an adrenocorticotropic hormone (ACTH) solution (0.5 mg/2 L isotonic NaCl solution per cow) or isotonic NaCl solution in a 2×2 crossover design. ACTH infusion stimulated cortisol secretion and increased plasma cortisol concentrations for 18 h (P<0.001), leading to an elevated plasma glucose concentration until 36 h (P<0.001). Plasma calcium and magnesium concentrations in ACTH-infused cows fluctuated within normal ranges, whereas hypophosphatemia was observed unequivocally. The biochemical bone resorption markers tartrate-resistant acid phosphatase 5b and hydroxyproline decreased following ACTH infusion (P<0.001 and P=0.003, respectively). Similarly, the bone formation marker, bone-specific alkaline phosphatase, decreased continuously until 72 h after the ACTH infusion (P<0.001). These results demonstrate that increased secretion of cortisol via a 12-h ACTH infusion disrupted homeostasis of inorganic phosphate and suppressed bone metabolism in ovariectomized cows without involving gonadal steroid hormones.
authors.affiliation: United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan. danilkim73@gmail.com
authors.forename: D
authors.initials: D
authors.lastname: Kim
authors.forename: N
authors.initials: N
authors.lastname: Yamagishi
authors.forename: B
authors.initials: B
authors.lastname: Devkota
authors.forename: K
authors.initials: K
authors.lastname: Furuhama
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D001786:Blood Glucose; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000378:metabolism*; D002417:Cattle / Q000378:metabolism*; D018592:Cross-Over Studies; D004334:Drug Administration Schedule; D006706:Homeostasis / Q000187:drug effects*; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D008903:Minerals / Q000378:metabolism; D010052:Ovariectomy; D012965:Sodium Chloride
chemical_list: D001786:Blood Glucose; D008903:Minerals; D012965:Sodium Chloride; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone