title: Comparison of two doses of aqueous bovine thyrotropin for thyroid function testing in dogs.
abstract: Thyroid function was evaluated in 20 healthy dogs by thyrotropin (TSH) response testing. Two dose regimens were used: 5 IU of TSH given IV and 1 IU of TSH given IV. Blood samples were collected prior to and at 4 and 6 hours after TSH administration. Serum was obtained and analyzed for total 3,5,3'-tri-iodothyronine and thyroxine (T4) concentrations by radioimmunoassay. All dogs were classified as euthyroid on the basis of response to 5 IU of TSH at 4 and 6 hours. The 1-IU dose of TSH failed to induce adequate increase in T4 concentration in 7 dogs at 4 and 6 hours when the criteria for normal response were post-TSH serum concentration T4 greater than or equal to 3.0 micrograms/dl and serum T4 increase by greater than or equal to 100% over baseline serum T4 concentration. One IU of TSH induced increase in serum T4 concentration over baseline; however, the increase was significantly (P less than 0.05) less than that in response to a 5-IU dose at 6 hours after administration of TSH.
authors.affiliation: Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32608.
authors.forename: K M
authors.initials: KM
authors.lastname: Beale
authors.forename: L J
authors.initials: LJ
authors.lastname: Helm
authors.forename: K
authors.initials: K
authors.lastname: Keisling
mesh_terms: D000818:Animals; D001835:Body Weight; D002417:Cattle; D004285:Dogs / Q000502:physiology*; D013960:Thyroid Function Tests / Q000662:veterinary*; D013961:Thyroid Gland / Q000502:physiology*; D013972:Thyrotropin / Q000008:administration & dosage
chemical_list: D013972:Thyrotropin