A fase estrogênica altera a resposta do osso e do metabolismo mineral de ratas com hipertireoidismo?
AUTOR(ES)
Ocarino, N.M., Serakides, R., Nunes, V.A.
FONTE
Arquivo Brasileiro de Medicina Veterinária e Zootecnia
DATA DE PUBLICAÇÃO
2003-08
RESUMO
The effect of the estrogenic phase in the bone and in the mineral metabolism was studied in Wistar adult female rats kept under euthyroidism or hyperthyroidism for 60 days. The rats were divided, according to the stage of the estrous cycle, into four groups: 1) euthyroid (proestrus-estrus), 2) euthyroid (metaestrus-diestrus), 3) hyperthyroid (proestrus-estrus), and 4) hyperthyroid (metaestrus-diestrus). After 60 days the blood plasma was collected and the concentrations of free T4, estradiol, progesterone, calcium, phosphorus, and of alkaline phosphatase were determined. The bones (femur and tibia) were analysed microscopically. Despite of the functional state of the thyroid, the levels of estrogen were significantly higher in the proestrus-estrus. The estrogenic phase increased the plasmatic concentration of calcium significantly in the euthyroid rats but it did not alter the levels of phosphorus and alkaline phosphatase. In the hyperthyroid state no significant differences in the plasmatic concentrations of calcium, phosphorus and alkaline phosphatase throughout the cycle were found. The phases of the cycle did not also influence the bone morphology in the euthyroid and hyperthyroid states. It was concluded that the estrogenic phase increases the plasmatic concentration of calcium, even without altering the bone morphology of the euthyroid rats. In addition the estrogenic phase does not increase the plasmatic calcium and it does not modify the response of the bone as well as of the mineral metabolism under effect of the hyperthyroidism.
ASSUNTO(S)
rato hipertireoidismo osso ciclo estral
Documentos Relacionados
- Efeito da associação hipertireoidismo-castração no osso de ratas adultas
- Qual a melhor opção para tratamento medicamentoso do hipertireoidismo?
- Influência da deficiência estrogênica e do tratamento com tibolona no osso trabecular e cortical avaliada pelo sistema de radiografia computadorizada em ratas
- Resposta da paratireóide de ratas às variações do cálcio e fósforo plasmáticos no hipertireoidismo e hipogonadismo
- Densidade mineral óssea em cadelas submetidas à ovarioisterectomia com e sem reposição estrogênica oral