Produção Nacional
Revisado por pares
IMPAIRED CYCLIC-AMP RESPONSE TO THYROTROPHIN IN CONGENITAL HYPOTHYROIDISM WITH THYROGLOBULIN DEFICIENCY
1979; Oxford University Press; Volume: 92; Issue: 1 Linguagem: Inglês
10.1530/acta.0.0920062
ISSN1479-683X
AutoresGeraldo Medeiros‐Neto, Meyer Knobel, Marcello D. Bronstein, José Pascoal Simonetti, Fadlo Fraige Filho, E Mattar,
Tópico(s)Neuroscience of respiration and sleep
ResumoABSTRACT A 19 year old man had congenital hypothyroidism and severely retarded development. His thyroid gland was not enlarged and laboratory findings included low serum concentration of T 4 (2.8 μg/100 ml) and T 3 (16 ng/100 ml) with a high level of TSH (52 μU/ml) that rose to 192 μU/ml after TRH. 131 I uptake by the thyroid was normal (41.5 % at 24 h) and did not show a normal increase after exogenous TSH administration (49.5 % at 24 h). The perchlorate discharge test was negative and no antibodies against thyroid antigens were found. Studies on the biopsy specimen revealed low iodide trapping by the thyroid slices and no formation of cyclic AMP after TSH was added to the medium. The endogenous TSH of the patient was biologically active increasing cyclic adenosine monophosphate c-AMP concentration in normal thyroid slices. No thyroglobulin was found in the thyroid tissue either by immunological or ultracentrifugational methods. An increased proportion of iodoalbumin was present in the serum. We postulate that the fundamental defect in this gland is an impaired generation of c-AMP by the defective thyroid cell and deficiency of thyroglobulin formation resulting in inadequate thyroxine and triiodothyronine synthesis.
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