title: Pharmacokinetics and selected pharmacodynamics of cobalt following a single intravenous administration to horses.
abstract: Cobalt has been used by human athletes due to its purported performance-enhancing effects. It has been suggested that cobalt administration results in enhanced erythropoiesis, secondary to increased circulating erythropoietin (EPO) concentrations leading to improvements in athletic performance. Anecdotal reports of illicit administration of cobalt to horses for its suspected performance enhancing effects have led us to investigate the pharmacokinetics and pharmacodynamic effects of this compound when administered in horses, so as to better regulate its use. In the current study, 18 horses were administered a single intravenous dose of cobalt chloride or cobalt gluconate and serum and urine samples collected for up to 10 days post administration. Cobalt concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS) and pharmacokinetic parameters determined. Additional blood samples were collected for measurement of equine EPO concentrations as well as to assess any effects on red blood cell parameters. Horses were observed for adverse effects and heart rate monitored for the first 4 h post administration. Cobalt was characterized by a large volume of distribution (0.939 L/kg) and a prolonged gamma half-life (156.4 h). Cobalt serum concentrations were still above baseline values at 10 days post administration. A single administration of cobalt had no effect on EPO concentrations, red blood cell parameters or heart rate in any of the horses studied and no adverse effects were noted. Based on the prolonged gamma half-life and prolonged residence time, regulators should be able to detect administration of a single dose of cobalt to horses.
authors.affiliation: K.L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, 620 West Health Science Drive, Davis, CA, 95616, USA.|Department of Veterinary Molecular Biosciences, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA.
authors.forename: H K
authors.initials: HK
authors.lastname: Knych
authors.affiliation: School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Arthur
authors.affiliation: K.L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, 620 West Health Science Drive, Davis, CA, 95616, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Mitchell
authors.affiliation: California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, 620 West Health Science Drive, Davis, CA, 95616, USA.
authors.forename: I
authors.initials: I
authors.lastname: Holser
authors.affiliation: Department of Veterinary Molecular Biosciences, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA.|California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California, 620 West Health Science Drive, Davis, CA, 95616, USA.
authors.forename: R
authors.initials: R
authors.lastname: Poppenga
authors.affiliation: University of Kentucky Veterinary Diagnostic Laboratory, Department of Veterinary Science, University of Kentucky, 1490 Bull Lea Road, Lexington, KY, 40511, USA.
authors.forename: L L
authors.initials: LL
authors.lastname: Smith
authors.affiliation: University of Kentucky Veterinary Diagnostic Laboratory, Department of Veterinary Science, University of Kentucky, 1490 Bull Lea Road, Lexington, KY, 40511, USA.
authors.forename: M N
authors.initials: MN
authors.lastname: Helm
authors.affiliation: LGC Science, Inc., 1745 Alysheba Way #160, Lexington, KY, 40509, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Sams
authors.affiliation: University of Kentucky Veterinary Diagnostic Laboratory, Department of Veterinary Science, University of Kentucky, 1490 Bull Lea Road, Lexington, KY, 40511, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Gaskill
mesh_terms: D061605:Administration, Intravenous; D000818:Animals; D003035:Cobalt / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D006736:Horses / Q000378:metabolism*; D008297:Male; D058573:Performance-Enhancing Substances / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D010865:Pilot Projects
chemical_list: D058573:Performance-Enhancing Substances; D003035:Cobalt
keywords: cobalt; detection; horses; pharmacokinetics