دورية أكاديمية
Concentrations of thyroid hormones and iodothyronine binding proteins in serum of the koala (Phascolarctos cinereus).
| العنوان: | Concentrations of thyroid hormones and iodothyronine binding proteins in serum of the koala (Phascolarctos cinereus). |
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| المؤلفون: | Lawson VJ; Department of Zoology, University of Queensland., Curtis AJ, Michelangeli VP, Stockigt JR, Carrick FN, Barlow JW |
| المصدر: | Australian veterinary journal [Aust Vet J] 1996 Jul; Vol. 74 (1), pp. 55-8. |
| نوع المنشور: | Journal Article |
| اللغة: | English |
| بيانات الدورية: | Publisher: Wiley-Blackwell Pub Country of Publication: England NLM ID: 0370616 Publication Model: Print Cited Medium: Print ISSN: 0005-0423 (Print) Linking ISSN: 00050423 NLM ISO Abbreviation: Aust Vet J Subsets: MEDLINE |
| أسماء مطبوعة: | Publication: Oxford : Wiley-Blackwell Pub. Original Publication: New South Wales : Australian Veterinary Association |
| مواضيع طبية MeSH: | Marsupialia/*blood , Thyrotropin/*blood , Thyroxine/*blood , Triiodothyronine/*blood, Animals ; Blood Proteins/analysis ; Blood Proteins/metabolism ; Female ; Male ; Prealbumin/analysis ; Prealbumin/metabolism ; Protein Binding ; Reference Values ; Serum Albumin/analysis ; Serum Albumin/metabolism ; Thyroxine/metabolism |
| مستخلص: | Objective: To examine circulating total and free thyroid hormone (T3 and T4) concentrations, determine serum iodothyronine binding characteristics and estimate thyroid stimulating hormone (TSH) activity in sera of coastal and inland koalas. Design: A prospective study. Procedure: Koala serum T3 and T4 were measured by radioimmunoassay. T4 binding parameters were determined by radioligand binding and electrophoresis. Koala TSH values were determined by bioassay. Results: Mean total T4 concentrations were 3.2 +/- 2.1 nM although values were significantly higher in inland-dwelling females in comparison to coastal-dwelling males. Free T4 was 3.3 +/- 2.1 pM. Total and free T3 were 0.4 +/- 0.2 nM and 1.4 +/- 0.9 pM respectively, although these values were at the lower end of the assay detection limit and should be viewed with reservation. Electrophoresis of [125I]-T4-labelled serum revealed only two proteins of electrophoretic mobility similar to human transthyretin (TTR) and albumin. Scatchard analysis of T4 binding to serum gave a curvilinear plot, which could be resolved into two binding sites with affinities identical to that of TTR and albumin but both of low concentration. The bioactivity of the TSH present in the sera was measured using a cell line (JP09) transfected with the human TSH receptor. The mean level of stimulation found in the sera corresponded to a bovine TSH activity of less than 10 mU/L. Conclusion: These results suggest that the serum concentrations of free and total thyroid hormones in koalas are low compared to other marsupials and very low compared to eutherian mammals. The mechanism of maintenance of euthyroidism in this species remains to be determined. |
| المشرفين على المادة: | 0 (Blood Proteins) 0 (Prealbumin) 0 (Serum Albumin) 06LU7C9H1V (Triiodothyronine) 9002-71-5 (Thyrotropin) Q51BO43MG4 (Thyroxine) |
| تواريخ الأحداث: | Date Created: 19960701 Date Completed: 19970213 Latest Revision: 20190718 |
| رمز التحديث: | 20221213 |
| DOI: | 10.1111/j.1751-0813.1996.tb13736.x |
| PMID: | 8894007 |
| قاعدة البيانات: | MEDLINE |
Full Text Finder | تدمد: | 0005-0423 |
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| DOI: | 10.1111/j.1751-0813.1996.tb13736.x |