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Mouse Mammary Epithelial Cells form Mammospheres During Lactogenic Differentiation
Published on: October 6, 2009
Expresión de un péptido similar a la hormona paratiroidea que moviliza el calcio en el tejido mamario lactante
1Department of Bone Biology and Osteoporosis Research, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486.
Science (New York, N.Y.)
|October 14, 1988
Resumen
El péptido parecido a la hormona paratiroidea (PTH-LP) se encuentra en las glándulas mamarias lactantes, lo que sugiere un papel en la transferencia de calcio a la leche durante la lactancia. Su expresión está regulada rápidamente por el estímulo de succión.
Área de la Ciencia:
- Endocrinología Endocrinología.
- Biología Molecular Biología Molecular
- La fisiología de la lactancia fisiología de la lactancia.
Sus antecedentes:
- El péptido parecido a la hormona paratiroidea (PTH-LP) está relacionado con la hipercalcemia de la malignidad.
- Sus funciones fisiológicas permanecen en gran medida sin caracterizar.
Objetivo del estudio:
- Para investigar el papel fisiológico de PTH-LP.
- Para identificar los tejidos que expresan PTH-LP y su función durante la lactancia.
Principales métodos:
- Análisis de ARN de tejidos de ratas.
- La clonación del ADN complementario PTH-LP de la rata.
- Análisis de la actividad de la adenilato ciclasa dependiente de la hormona paratiroidea.
Principales resultados:
- Se detectó un ARN mensajero de 1,5 kilobases para PTH-LP en las glándulas mamarias de ratas lactantes.
- La expresión del ARN mensajero PTH-LP es específica de la lactancia y responde rápidamente al estímulo de succión.
- El ADNc clonado PTH-LP confirmó la similitud con el homólogo humano.
- Los extractos de tejido mamario en lactancia estimulan la adenilato ciclasa.
Conclusiones:
- PTH-LP probablemente juega un papel fisiológico en la lactancia.
- Puede funcionar como una hormona para movilizar o transferir el calcio a la leche.
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