-
Views
-
Cite
Cite
STACY PSYCHOYOS, S. MA DANIEL, ANDREW J. CZERNIK, HELEN SCHLANGEL BOWERS, CHARLOTTE D. ATKINS, CAROL A. MALICKI, WILLIAM D. CASH, Thyromimetic Activity of Methylene-Bridged Thyroid Hormone Analogs, Endocrinology, Volume 92, Issue 1, 1 January 1973, Pages 243–250, https://doi.org/10.1210/endo-92-1-243
- Share Icon Share
Methylene—bridged thyroid hormone analogs, in which a methylene group replaces the oxygen atom bridging the two aromatic rings, were evaluated for thyromimetic activity in the rat. All five analogs tested resembled qualitatively the corresponding diphenyl ethers with respect to their ability to increase mitochondrial glycerophosphate dehydrogenase (GPD) activity in various organs and tissues. The methylene—bridged compounds exerted effects typical of the diphenyl ethers on body wt and on the wts of various organs and tissues. The methylene-bridged analogs of T4 and T3 were tested for effects upon metabolic rate and were found to increase oxygen consumption. The analog corresponding to T4 was evaluated in thyroidectomized rats and was found to elevate GPD activity, to increase oxygen consumption, and to exert T4-like effects on the wts of various organs. The methylene-bridged compounds resembled qualitatively the diphenyl ethers with respect to their ability to inhibit lipid peroxidation in vitro.
Although the methylene—bridged analogs were consistently less potent in all tests than the corresponding oxygen—bridged compounds, some were nonetheless highly active substances. For example, under the experimental conditions that prevailed in this study, the racemic methylene—bridged compound corresponding to T3 was equivalent in potency to L–T4. The ability of the methylene—bridged compounds to exert strong thyromimetic effects indicates clearly that an ether or thioether linkage is not, as previously believed, a structural requisite for thyroid hormone—like activity. (Endocrinology92: 243, 1973)