RESUMO
The effect of ovine prolactin on the renal 25-hydroxycholecalciferol-1-hydroxylase was studied in the chick. Prolactin was found to increase the activity of this enzyme in both long-term and short-term experiments. In the long term, 7 days treatment with prolactin caused a marked stimulation of the 1-hydroxylase activity, however this effect was only seen when the enzyme was assayed 2-3 hours after the final injection of prolactin. A single subcutaneous injection of prolactin was also effective in increasing the 1-hydroxylase activity, this effect was maximal at one hour and had largely disappeared 3 hours after prolactin administration.
Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Rim/metabolismo , Prolactina/farmacologia , Esteroide Hidroxilases/metabolismo , Vitamina D/metabolismo , Animais , Galinhas , Rim/efeitos dos fármacos , Ovinos , Vitamina D/farmacologia , Deficiência de Vitamina D/metabolismoAssuntos
Hidroxicolecalciferóis/isolamento & purificação , Animais , Galinhas , Cromatografia por Troca Iônica , Estudos de Avaliação como Assunto , Vidro , Hidroxicolecalciferóis/análogos & derivados , Hidroxicolecalciferóis/metabolismo , Rim/metabolismo , Métodos , Espectrofotometria Ultravioleta , Fatores de TempoRESUMO
Immunoreactive calcitonin was found in extracts of seven out of eight consecutive breast carcinomas and four selected lung carcinomas, but not in extracts of benign breast lesions or normal tissues. This suggests that the high plasma calcitonin levels observed in patients with a wide variety of cancers reflect ectopic production of calcitonin by cancer tissue, and that the radioimmunoassay for calcitonin could prove to be of value in the detection and management of malignant disease, particularly breast cancer.
Assuntos
Neoplasias da Mama/análise , Calcitonina/análise , Neoplasias Pulmonares/análise , Animais , Bioensaio , Mama , Neoplasias da Mama/diagnóstico , Calcitonina/sangue , Feminino , Hormônios Ectópicos , Humanos , Hipocalcemia , Radioimunoensaio , Ratos , Neoplasias da Glândula Tireoide/análiseRESUMO
Twenty-three out of 28 patients with metastatic breast carcinoma and one out of 13 patients with localised disease had raised levels of plasma immunoreactive calcitonin. Monolayer cultures of breast carcinomas maintained for up to 10 weeks released immunoreactive calcitonin, and a primary breast carcinoma passaged in "nude" mice for over a year contained material immunologically and chromatographically resembling the monomeric form of human calcitonin. These studies indicate that breast carcinomas can produce calcitonin and that plasma calcitonin measurements may be useful in staging patients with breast carcinomas.