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


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.


alopecia biopsy dog hormone iodothyronine serum skin thyroid thyroxine 



body weight




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






thyrotropin-releasing hormone


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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