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Regulación de la afluencia de calcio por medio de segundos mensajeros en los mastocitos de rata
R Penner1, G Matthews, E Neher
1Max-Planck-Institut für Biophysikalische Chemie, Göttingen, FRG.
Nature
|August 11, 1988
Resumen
Los mastocitos de rata exhiben aumentos bifásicos de calcio, con una nueva corriente de cloruro activada por cAMP que interactúa con la afluencia de calcio dependiente de IP3 para mantener los niveles de calcio intracelular para procesos como la exocitosis.
Área de la Ciencia:
- Biología celular Biología celular.
- Fisiología Fisiología Fisiología.
Sus antecedentes:
- Los aumentos bifásicos en el calcio intracelular son comunes en las células no excitables después de la estimulación.
- La elevación sostenida del calcio es crucial para varios procesos celulares.
Objetivo del estudio:
- Investigar los mecanismos subyacentes a la elevación sostenida del calcio intracelular en los mastocitos peritoneos de rata.
- Explorar la interacción entre las corrientes de cloruro activadas por cAMP y la afluencia de calcio dependiente de IP3.
Principales métodos:
- Registros electrofisiológicos para medir las corrientes de cloruro.
- Imágenes de calcio para monitorear las concentraciones intracelulares de calcio.
- Protocolos de estimulación para inducir la liberación y la afluencia de calcio.
Principales resultados:
- Se identificó una corriente de cloruro activada por cAMP y Ca en los mastocitos peritoneos de rata.
- Esta corriente de cloruro interactúa con el influjo de calcio dependiente de IP3.
- La interacción mantiene la elevación del calcio intracelular después de la liberación inicial inducida por IP3.
Conclusiones:
- Un nuevo mecanismo que involucra corrientes de cloruro activadas por cAMP y una afluencia de calcio dependiente de IP3 mantiene el calcio intracelular en los mastocitos.
- Esta interacción proporciona un sistema flexible para modular los procesos dependientes del calcio, incluida la exocitosis.
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