Theophylline Increases the Uptake of Radioiodine by Mouse Thyroid
Journal of Korean Medical Science
;
: 704-709, 2004.
Artigo
em Inglês
| WPRIM
| ID: wpr-123125
ABSTRACT
Diagnostic and therapeutic use of radioiodine in the management of thyroid disorders depends on the ability of thyroid cells to concentrate radioiodine, a process that is regulated by the intracellular increase in cAMP. We hypothesized that theophylline, a drug known to increase intracellular cAMP via inhibition of phosphodiesterase, could increase thyroidal radioiodine uptake. We tested this effect in vivo, using C57BL/6j mice, and in vitro, using Fisher rat thyroid (FRTL-5) cells. One mouse received 2.5mg theophylline i.p., whereas a control mouse received only saline. Twenty-hours after theophylline, mice were injected with 10mu Ci Na(125)I in 0.1 mL saline through the tail vein. Mean thyroidal (125)I activity was 3.3-fold higher in theophylline-treated mice than in their respective controls. Radioiodine uptake and intracellular cAMP production of FRTL-5 cells were increased by a relatively low concentration of theophylline (1mu M). Intracellular cAMP increased up to 30 min and then declined in response to 1mu M theophylline. Sera from theophylline-treated mice stimulated (125)I uptake and intracellular cAMP production by FRTL-5 cells. These findings show that theophylline can enhance radioiodine uptake by thyrocytes in vivo and in vitro. The in vitro effects of theophylline on both radioiodine uptake and cAMP production in a dose-dependent manner are consistent with an action mediated by phosphodiesterase inhibition.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Teofilina
/
Glândula Tireoide
/
Vasodilatadores
/
Proteínas Sanguíneas
/
Células Cultivadas
/
AMP Cíclico
/
Radioisótopos do Iodo
/
Camundongos Endogâmicos C57BL
Limite:
Animais
Idioma:
Inglês
Revista:
Journal of Korean Medical Science
Ano de publicação:
2004
Tipo de documento:
Artigo
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