Nitric oxide/cGMP signalling inhibits TSH-stimulated iodide uptake and expression of thyroid peroxidase and thyroglobulin mRNA in FRTL-5 thyroid cells

BAZZARA LG, VÉLEZ ML, COSTAMAGNA ME, CABANILLAS AM, FOZZATTI L, LUCERO AM, PELLIZAS CG, MASINI-REPISO AM.

THYROID

Mary Ann Libert, Inc

Lugar: New York, USA; Año: 2006

1050-7256

font face="Arial" size="3"> Previous reports indicated that nitric oxide (NO) inhibited differentiation characteristics in thyroid follicular cells. The action of NO on the expression of genes related to thyroid hormone biosynthesis has not been explored. This work aimed to analyse the role of the NO/guanylyl cyclase/cyclic GMP (cGMP) pathway on iodide uptake and TPO and thyroglobulin (Tg) gene expression in TSH-stimulated thyroid cells FRTL-5. The NO donor sodium nitroprusside (SNP) inhibited iodide uptake in a concentration (50-500 m mol/l) and time (24-72 h) dependent manner in TSH (500 m U/ml)-stimulated cells. A reduction of TPO and Tg mRNA expression (Northern-blot) after SNP addition was observed. Treatment for 24-48 h with 50-500 m mol/l SNP increased cGMP levels (RIA) in a concentration and time dependent fashion whereas cAMP level (RIA) was decreased by 500