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Tri iodo thyronine stimulates specifically growth hormone messenger rna in rat pituitary tumor cells

Proceedings of the National Academy of Sciences of the United States of America 74(5): 2054-2058

Tri iodo thyronine stimulates specifically growth hormone messenger rna in rat pituitary tumor cells

In a cell free protein synthesizing system from a rabbit reticulocyte lysate, total RNA extracted from cultured rat pituitary tumor (GH3) cells directed, in a dose related manner, the synthesis of proteins that were precipitated by antisera specific to rat growth hormone (somatotropin) and rat prolactin. A marked decrease in growth hormone secretion and growth hormone mRNA activity was observed when cells were grown in a medium deficient in thyroid hormone. Addition of triiodothyronine in physiologic amounts prevented and completely reversed this effect within 48 h. Thyroid hormone had no effect on prolactin secretion or prolactin mRNA activity. These data suggest that thyroid hormone may stimulate synthesis of growth hormone through induction of transcriptional activity. The possibility of an additional effect at the posttranscriptional level was not excluded. Although thyroid hormone is believed to have a general effect on a variety of metabolic processes, some effects, at the molecular level, may be quite selective, as indicated by the observed changes in growth hormone but not prolactin mRNA activity. The GH3 cell model is useful in the study of triiodothyronine action because of independence from secondary hormonal effects caused by hypothyroidism and because simultaneous measurement of prolactin mRNA activity serves as a unique internal control.

Accession: 006840157

Related references

Kumara-Siri, M.H.; Surks, M.I., 1985: Regulation of growth hormone messenger rna synthesis by 3 5 3' triiodo l thyronine in cultured growth hormone producing rat pituitary tumor cells gc cells dissociation between nuclear iodothyronine receptor concentration and growth hormone messenger rna synthesis during the dna synthesis phase of the cell cycle. 3,5,3'-Triiodo-L-thyronine (T3) regulates the growth rate and GH production of cultured GC cells, a rat piutuitary tumour cell line. We have previously demonstrated a parallel increase in cellular content of DNA and nuclear T3 glucocorticoid...

Silva, J.E.; Larsen, P.R., 1978: Contributions of plasma tri iodo thyronine and local thyroxine mono deiodination to tri iodo thyronine to nuclear tri iodo thyronine receptor saturation in pituitary liver and kidney of hypo thyroid rats further evidence relating saturation of pituitary nuclear tri iodo thyronine receptors and the acute inhibition of thyroid stimulating hormone release. Injections of triiodothyronine (T3) and thyroxine (T4) into chronically hypothyroid rats were used to evaluate the contribution of intracellular T4 to T3 conversion to nuclear T3 in pituitary, liver and kidney, and to correlate the occupancy of pi...

Brocas H.; Seo H.; Refetoff S.; Vassart G., 1978: Early in vitro induction of rat pituitary growth hormone messenger rna by tri iodo thyronine. Thyroid hormone stimulates rat pituitary GH [growth hormone] synthesis and GH mRNA activity and concentration. The earliest demonstration of increase in GH mRNA activity was 24 h following T3 addition, whereas stimulation of GH synthesis was obser...

Seo, H.; Vassart, G.; Brocas, H.; Refetoff, S., 1977: Triiodothyronine stimulates specifically growth hormone mRNA in rat pituitary tumor cells. In a cell-free protein-synthesizing system from a rabbit reticulocyte lysate, total RNA extracted from cultured rat pituitary tumor (GH3) cells directed, in a dose-related manner, the synthesis of proteins that were precipitated by antisera specif...

Larsen P.R.; Silva J.E.; Dick T.E., 1978: Relative contributions of local thyroxine tri iodo thyronine to 3 5 3 tri iodo thyronine conversion and plasma tri iodo thyronine to nuclear tri iodo thyronine in rat anterior pituitary liver and kidney. Clinical Research 26(3): 492A

Wong C.C.; Von Zur Muehlen A.; Doehler K D., 1980: Effects of tri iodo thyronine thyroxine and iso propyldiiodo thyronine on thyroid stimulating hormone in serum and pituitary gland and on pituitary concentrations of prolactin growth hormone luteinizing hormone and follicle stimulating hormone in hypo thyroid rats. Replacement of 3'-halogen of the triiodothyronine (T3) molecule by a propyl-group produces a thyromimetic analog, 3'-isopropyl-3,5-diiodo-L-thyronine (T2iPr), with high biological potency. A serum thyroid-stimulating hormone (thyrotropin...

Anonymous, 1979: The concentrations of thyroxine tri iodo thyronine reverse tri iodo thyronine 3 3 di iodo thyronine and 3 5 di iodo thyronine in serum and thyrotropin releasing hormone in cerebro spinal fluid in endogenous depression

Surks, M.I.; Oppenheimer, J.H., 1977: Concentration of l thyroxine and l tri iodo thyronine specifically bound to nuclear receptors in rat liver and kidney quantitative evidence favoring a major role of tri iodo thyronine in thyroid hormone action. To estimate the relative contribution of L-triiodothyronine (T3) and L-thyroxine (T4) to thyroidal effects, the concentration of iodothyronine bound to specific hepatic nuclear receptor sites was measured by 3 different techniques: specific radioi...

Samuels H.H.; Stanley F.; Casanova J., 1979: Relationship of receptor affinity to the modulation of thyroid hormone nuclear receptor levels and growth hormone synthesis by l tri iodo thyronine and iodo thyronine analogs in cultured gh 1 cells. L-Triiodothyronine (L-T3) induces an increase in growth hormone [GH] synthesis and mRNA in cultured GH1 cells, a rat pituitary cell line. In addition to regulating the GH response, L-T3 elicits a time- and dose-dependent reduction in the level of...

Gacs G.; Banos C., 1981: The effect of growth hormone on the plasma levels of thyroxine free thyroxine tri iodo thyronine reverse tri iodo thyronine and thyroxine binding globulin in hypo pituitary patients. The plasma concentrations of thyroxine (T4), free-T4, triiodothyronine (T3), reverse [r] T3 TSH [thyrotropin] and thyroxine-binding globulin (TBG) were measured in 19 children suffering from idiopathic growth hormone deficiency. Blood was taken be...