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Las condiciones del flujo arterial regulan a la baja la trombomodulina en el endotelio de la vena safena
M Gosling1, J Golledge, R J Turner
1Department of Vascular Surgery, Imperial College School of Medicine at Charing Cross, Charing Cross Hospital, London, UK.
Circulation
|March 2, 1999
Resumen
Las condiciones de flujo arterial disminuyen rápidamente la trombomodulina en injertos de venas safenales, aumentando el riesgo de trombosis. Este efecto es dependiente del calcio y puede prevenirse bloqueando los canales de calcio, lo que sugiere un objetivo terapéutico para la patencia del injerto de derivación.
Área de la Ciencia:
- Biología Vascular Biología Vascular
- La bioquímica es la bioquímica.
- Cirugía cardiovascular La cirugía cardiovascular es una cirugía cardiovascular.
Sus antecedentes:
- Los injertos de venas safenas en la circulación arterial pueden perder propiedades antitrombogénicas.
- Esta atenuación puede conducir a la trombosis y la oclusión de los injertos de derivación arterial.
Objetivo del estudio:
- Investigar cómo las condiciones del flujo arterial afectan a las proteínas reguladoras de la trombosis en la vena safena humana.
- Para determinar si el bloqueo de los canales iónicos influye en estos cambios.
Principales métodos:
- Circuito de flujo de la vena safena humana ex vivo que simula las condiciones arteriales.
- Cuantificación de la trombomodulina y el factor de tejido utilizando Western blotting y inmunohistoquímica.
- Evaluación de la generación de proteína C activada y el efecto de los bloqueadores de los canales de calcio (Gd3+, nifedipina).
Principales resultados:
- El flujo arterial redujo significativamente la concentración de trombomodulina y activó la generación de proteína C.
- La reducción de la trombomodulina se relacionó con los mecanismos dependientes del calcio.
- El bloqueo de los canales de calcio (Gd3+, nifedipina) impidió la regulación a la baja de la trombomodulina.
- Los niveles de factor tisular se mantuvieron bajos, pero aumentaron con nifedipina.
Conclusiones:
- El endotelio de la vena safena desregula rápidamente la trombomodulina bajo el flujo arterial.
- Esta regulación a la baja es dependiente del calcio y limita la activación de la proteína C.
- Dirigirse a los canales de calcio puede preservar la función del injerto y prevenir la oclusión.
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