Nitric oxide production is not involved in the effects of interleukin-1 beta on cAMP, thyroglobulin and interleukin-6 in TSH-stimulated human thyroid cells.
Interleukin (IL)-1 inhibits the function of insulin-producing rat pancreatic beta-cells in vitro and in vivo, and it has been postulated that the IL-1 effect is mediated through the cytokine inducible nitric oxide (NO) synthase. IL-1 inhibits the function of cultured human thyroid cells too, and in this study human thyroid cell production of NO in response to the TSH-stimulated influence of IL-1 beta (10(5) U/l) and TNF-alpha (10(6) U/l), alone or in combination was measured. IL-1 beta, but not TNF-alpha, induced an increase in nitrite production, which was significantly reduced by the competitive inhibitor of nitric oxide synthase L-NG-monomethyl-arginine (L-NMMA) (0.1 mmol/L and 0.5 mmol/L). However, the nitrite production was unrelated to the IL-1 beta-induced inhibition of thyroglobulin (Tg) and cyclic AMP (cAMP) and the IL-1 beta-induced IL-6 production. Thus, it is unlikely that NO is a second mediator of the demonstrated effects of IL-1 beta and TNF-alpha on human thyroid cells in culture.
Rasmussen
A K
AK
Medical Department P, Rigshospitalet, University of Copenhagen, Denmark.
Di Marco
R
R
Diamant
M
M
Feldt-Rasmussen
U
U
Bendtzen
K
K
D002478:Cells, Cultured; D000242:Cyclic AMP / Q000096:biosynthesis*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D015850:Interleukin-6 / Q000096:biosynthesis*; D009569:Nitric Oxide / Q000096:biosynthesis*; D009573:Nitrites / Q000378:metabolism; D013954:Thyroglobulin / Q000096:biosynthesis / Q000187:drug effects*; D013961:Thyroid Gland / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D013972:Thyrotropin / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D007375:Interleukin-1; D015850:Interleukin-6; D009573:Nitrites; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D013972:Thyrotropin; D013954:Thyroglobulin; D000242:Cyclic AMP