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La activación de la entrada de Ca2+ en las células acinares por un trisfosfato de inositol no fosforilable
G S Bird1, M F Rossier, A R Hughes
1Calcium Regulation Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709.
Nature
|July 21, 1991
Resumen
El inositol 1,4,5-trisfosfato es esencial para la entrada del calcio (Ca2+) en las células lacrimales acinares del ratón. Este hallazgo aclara el papel de los fosfatos de inositol en las vías de señalización del calcio celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Fisiología Fisiología Fisiología.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La activación de los receptores desencadena la liberación de calcio intracelular (Ca2+) y su posterior entrada en la membrana plasmática.
- El inositol 1,4,5-trisfosfato media la liberación inicial de Ca2+, pero su papel en la entrada de Ca2+ es objeto de debate.
Objetivo del estudio:
- Investigar el papel del inositol 1,4,5-trisfosfato en la regulación de la entrada de Ca2+ en las células lacrimales acinares del ratón.
- Para determinar si el inositol 1,4,5-trisfosfato es necesario y suficiente para la entrada de Ca2+ activado por el receptor.
Principales métodos:
- Los fosfatos de inositol se introdujeron en las células acinares lacrimales del ratón mediante microinyección o perfusión con pinzas de parche.
- La concentración intracelular de calcio libre se midió utilizando la fluorescencia Fura-2.
- Los canales de potasio activados por calcio monitorearon la actividad de Ca2+ de la célula entera.
Principales resultados:
- Se encontró que el inositol 1,4,5-trisfosfato es tanto necesario como suficiente para la entrada de Ca2+ activado por el receptor.
- Estos hallazgos fueron consistentes en las configuraciones experimentales de microinyección y pinza de parche.
Conclusiones:
- El inositol 1,4,5-trisfosfato actúa como una señal crítica para iniciar la entrada de calcio (Ca2+) a través de la membrana plasmática.
- Este estudio resuelve la controversia que rodea el papel del inositol 1,4,5-trisfosfato en la homeostasis celular del calcio.
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