TSH and catecholamines: independent effects on active transport and iodine organification in isolated thyroid cells.
Catecholamines greatly stimulated iodine organification in thyroid cells isolated by trypsinization but failed to increase the cell-medium (C/M) ratio of 131I- or 99mTcO4- in the same cells preparation. Both TSH and catecholamines increased the concentration of organified iodine in thyroid cell despite the presence of active transport inhibitors, suggesting either the existence of a second thyroidal transport system or the possibility of an accelerated entry of anions into thyroid cells in the presence of stimulatory agents.
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002417:Cattle; D004077:Digoxin / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology*; D007455:Iodine / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology*; D010042:Ouabain / Q000494:pharmacology; D013268:Stimulation, Chemical; D013961:Thyroid Gland / Q000378:metabolism*; D013972:Thyrotropin / Q000494:pharmacology*
D010042:Ouabain; D004077:Digoxin; D013972:Thyrotropin; D007455:Iodine; D009638:Norepinephrine; D004837:Epinephrine