Published 1987 | Version v1
Journal article Metadata-only

Thyroid function in fasting rats: variations in 131I uptake and transient decrease in peroxidase activity

Creators

  • 1. Universidade do Estado, Rio de Janeiro, RJ (Brazil). Lab. de Fisiologia Endocrina
  • 2. Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst., de Biofisica

Description

Serum thyroxine and triiodothyronine, radioiodide thyroid uptak and thyroid peroxidase (TPO) activity were studied over a 2 to 5 day period in fasting rats treated (F+) or not (F-) with TSH. In F-rats, TPO activity was transiently decreased on the 3rd day, whereas in F+ it was always higher than in controls. On the 5th day, the 2 h thyroid uptake of 131I decreased in F-, while the 24 h uptake increased in both F- and F+. Serum T3 and T4 decreased in both fasting groups. Thus, not all effects of fasting on rat thyroid function are reverted by TSH administration, suggesting intrinsic impairment of glandular function. (author)

Abstract (Portuguese)

O soro da tiroxina, triiodotionina, o levantamento do radioiodo da tireoide e da atividade peroxidase da tireoide foram estudados por 2 a 5 dias no metabolismo de ratos tratados (F+) ou nao F-) com TSH (Thyroid stimulating hormone). Em ratos (F-) a atividade TPO foi decrescendo no 30 dia, enquanto que em F+ ela foi sempre maior que nos ratos controle. No 50 dia, a 2 horas a dosagem da tireoide de I131 diminuiu em F-, enquanto que na dosagem apos 24 horas aumentou em ambas F+ e F-. O soro T3 e T4 diminuiu em ambos os grupos. Nem todos os efeitos de metabolismo sobre a funcao tireoidiana dos ratos foram revertidos pela administracao do TSH, sugerindo deteriorizacao entrinseca da funcao glandular. (L.M.J)

Additional details

Publishing Information

Journal Title
Revista Brasileira de Pesquisas Medicas e Biologicas
Journal Volume
20
Journal Issue
3-4
Series
Rev. Bras. Pesqui. Med. Biol.
Journal Page Range
407-410
ISSN
0034-7310
CODEN
RBPMB

INIS

Country of Publication
Brazil
Country of Input or Organization
Brazil
INIS RN
21078844
Subject category
S63: RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS;
Descriptors DEI
IODINE 131; PEROXIDASES; RATS; THYROID
Descriptors DEC
ANIMALS; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BODY; CARBOXYLIC ACIDS; DAYS LIVING RADIOISOTOPES; ENDOCRINE GLANDS; ENZYMES; GLANDS; HETEROCYCLIC ACIDS; HETEROCYCLIC COMPOUNDS; INTERMEDIATE MASS NUCLEI; IODINE ISOTOPES; ISOTOPES; MAMMALS; NUCLEI; ODD-EVEN NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANS; OXIDOREDUCTASES; PORPHYRINS; RADIOISOTOPES; RODENTS; VERTEBRATES