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Imaging Local Ca2+ Signals in Cultured Mammalian Cells
Published on: March 3, 2015
Las oscilaciones citosólicas locales y globales de Ca2+ en las células exocrinas provocadas por los agonistas y el
P Thorn1, A M Lawrie, P M Smith
1Physiological Laboratory University of Liverpool, England.
Cell
|August 27, 1993
Resumen
Las bajas concentraciones de agonistas desencadenan picos locales de calcio en las células pancreáticas, activando corrientes iónicas cruciales para la secreción de líquidos. Estos picos ofrecen un mecanismo de señalización económico para el control celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Fisiología Fisiología Fisiología.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La estimulación del agonista a menudo conduce a las oscilaciones del calcio citosólico (Ca2+) en varios tipos de células.
- Estas señales de Ca2+ generalmente se inician cerca de la membrana plasmática y se propagan como ondas.
- El papel de la señalización localizada de Ca2+ en las células acinares pancreáticas requiere una mayor aclaración.
Objetivo del estudio:
- Para investigar la naturaleza de las señales de Ca2+ evocadas por bajas concentraciones fisiológicas de agonistas en células acinares pancreáticas de ratón.
- Determinar el origen y las características de estas señales de Ca2+ y su sensibilidad al bloqueo del receptor IP3.
- Comprender el significado fisiológico de estos eventos localizados de Ca2+ en la regulación de la función pancreática.
Principales métodos:
- Utilizó estimulación agonista submáxima en células acinares pancreáticas de un solo ratón.
- Monitoreo de la dinámica citosólica Ca2+ utilizando imágenes de fluorescencia.
- Aplicado el inositol intracelular 1,4,5-trisfosfato (IP3) y el antagonista del receptor IP3 heparina.
Principales resultados:
- Las bajas concentraciones de agonistas indujeron picos localizados de Ca2+ citosólico en el polo secretor de las células acinares pancreáticas.
- Estos picos locales eran sensibles al bloqueo por el antagonista del receptor IP3 heparina.
- Los picos podrían ocurrir de forma independiente, repetitiva o preceder a las señales globales de Ca2+, y fueron imitados por la aplicación IP3 intracelular.
- Estos picos de Ca2+ activaron las corrientes de Cl y de cationes dependientes de Ca2+.
Conclusiones:
- Los picos locales de Ca2+ de corta duración representan un mecanismo de señalización económico en las células acinares pancreáticas.
- Estos eventos localizados de Ca2+ son fisiológicamente significativos, controlando la actividad de los canales iónicos esenciales para la secreción de fluidos.
- Los hallazgos destacan un papel específico para la señalización localizada de Ca2+ en la regulación de la función exocrina pancreática.
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