Nitric Oxide/cGMP Signaling Inhibits TSH-Stimulated Iodide Uptake and Expression of Thyroid Peroxidase and Thyroglobulin mRNA in FRTL-5 Thyroid Cells

BAZZARA LEONARDO GABRIEL; VELEZ MARIA LAURA; COSTAMAGNA MARIA EUGENIA; CABANILLAS ANA MARIA; FOZZATTI LAURA; LUCERO ARIEL MAXIMILIANO; PELLIZAS CLAUDIA GABRIELA; MASINI-REPISO ANA MARIA

MARY ANN LIEBERT INC

Año: 2007 vol. 17 p. 717 - 717

Objective: Nitric oxide (NO) induces morphological and functional alterations in primary cultured thyroid cells. The aim of this paper was to analyze the direct influence of a long-termexposition to NO on parameters of thyroid hormone biosynthesis in FRTL-5 cells. Design: Cells were treated with the NO donor sodium nitroprusside (SNP) for 24–72 h. Main Outcome: SNP (50–500 mmol=L) reduced iodide uptake in a concentration-dependent manner. The inhibition of iodide uptake increased progressively with time and matched nitrite accumulation. SNP inhibited thyroperoxidase (TPO) and thyroglobulin (TG) mRNA expression in a concentration-dependent manner. SNP enhanced 30,50-cyclic guanosine monophosphate (cGMP) production. 30,50-cyclic adenosine phosphate (cAMP)generation was reduced by a high SNP concentration after 48 h. 8-Bromoguanosine 30,50-cyclic monophosphate (8-Br-cGMP), a cGMP analog, inhibited iodide uptake as well as TPO and TG mRNA expression. The cGMPdependent protein kinas