On the Origin and Mechanism of Action of a Thyroxine-Responsive Protein

Do thyroid hormones play a role in the regulation of pulmonary antioxidant development?

“…Previous studies have shown that the activities of pulmonary antioxidant enzymes (AOEs) in the fetus remain low until the last 10-15% of gestation (Frank & Sosenko 1987;Kelly & Rickett 1987). Glucose protected cells against H 2 0 2 toxicity with the efficiency significantly higher at pH 7.5 than 6.5 in accordance with previous observations [4, 51.…”

The Action of Thyroid Hormone

“…Following thyroidectomy, a depression in the activity of the enzyme tRNA methylase was shown to be corrected by T3 treatment (Kaplay & Sanadi, 1974). The response of the tRNA methylase parallels the increased incorporation of amino acids into the mitochondria and the appearance of T4 responsive proteins.…”

“…The mechanism of action of thyroid hormones at the leveI of translation is not clear, but could involve regulation of tRNA metabolism and distribution (Yang & Sanadi, 1969;Kaplay & Sanadi, 1974;Nielsen & Hascherneyer, 1976). Following thyroidectomy, a depression in the activity of the enzyme tRNA methylase was shown to be corrected by T3 treatment (Kaplay & Sanadi, 1974).…”

Plasma Amino Acids in Hypothyroid and Hypertyroid Rats

“…The incorporation of labeled amino acids into proteins (Michels, Cason and Sokoloff 1963;Carter, Faas and Wynn 1971) is related to the increase of target tissue oxygen utilization induced by thyroid hormones (Gordon and Hening 1944;Weiss and Sokoloff 1963). The action of thyroid hormones on protein synthesis would be, then, partly due to increased availability of energy produced in the oxidation of substrates by mitochondria (Hanson, Lindsay and Barker 1963;Primack, Tapley and Buchanan 1972) and specifically due to specific mRNA synthesis and translation (Garren, Richardson and Crocco 1967;Herd, Kaplay and Sanadi 1974;Kurtz, Sippel and Feigelson 1976;Seo, Vassart, Brocas and Refetoff 1977;Hulbert 1978); actions mediated by thyroid hormones binding to nuclear chromatin (Sterling 1979).…”