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Veterinary Research Communications

, Volume 18, Issue 3, pp 175–182 | Cite as

Impaired local deiodination of thyroxine to triiodothyronine in dogs with symmetrical truncal alopecia

  • P. Rudas
  • T. Bartha
  • J. Toth
  • V. L. Frenyo
Biochemistry

Abstract

Thyroid dysfunction causes certain dermatological alterations in dogs. Insufficient delivery of thyroid hormone to the skin may originate not only from inadequate thyroid function but also from impaired local activation of thyroxine in the target organ. Thyroid parameters and deiodination were investigated in healthy dogs (group C) and in dogs with cutaneous lesions associated with hypothyroidism (group H) or with a low-T3 syndrome (group LT). The ability of the skin to convert T4 to T3 was impaired in both groups H and LT but not in the controls. It is concluded that impaired local deiodination may contribute to skin problems in dogs.

Keywords

alopecia biopsy dog hormone iodothyronine serum skin thyroid thyroxine 

Abbreviations

bwt

body weight

DTT

dithiothreitol

PBS

phosphate-buffered saline (pH 7.5, 0.05 mol/L)

PTU

propylthiouracyl

RIA

radioimmunoassay

TRH

thyrotropin-releasing hormone

TSH

thyroid-stimulating hormone

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Copyright information

© Kluwer Academic Publishers bv 1994

Authors and Affiliations

  • P. Rudas
    • 1
  • T. Bartha
    • 1
  • J. Toth
    • 2
  • V. L. Frenyo
    • 1
  1. 1.Department of Physiology and BiochemistryUniversity of Veterinary Science, BudapestBudapestHungary
  2. 2.Department of SurgeryUniversity of Veterinary Science, BudapestBudapestHungary

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