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La protamina libera el factor relajante derivado del endotelio de las arterias sistémicas. Un posible mecanismo de
P J Pearson1, P R Evora, K Ayrancioglu
1Cardiac Surgical Research, Mayo Clinic, Rochester, Minn 55905.
Circulation
|July 1, 1992
Resumen
El sulfato de protamina, utilizado para revertir la heparina, puede causar hipotensión al liberar el factor de relajación derivado del endotelio (EDRF). Este estudio confirma que la protamina estimula la liberación de EDRF de las arterias, lo que explica sus efectos vasodilatadores.
Área de la Ciencia:
- Farmacología Cardiovascular Farmacología Cardiovascular
- La función endotelial es la función endotelial.
Sus antecedentes:
- El sulfato de protamina se utiliza para revertir los efectos anticoagulantes de la heparina.
- La administración de protamina puede causar hipotensión, potencialmente relacionada con la vasodilatación.
- La protamina contiene arginina, un precursor del óxido nítrico (NO), el componente activo del factor relajante derivado del endotelio (EDRF).
Objetivo del estudio:
- Investigar si la protamina estimula la liberación de EDRF, causando la vasodilatación y la hipotensión.
- Para dilucidar el mecanismo detrás de la hipotensión inducida por la protamina.
Principales métodos:
- Se estudiaron los anillos arteriales caninos (coronarios, femorales, renales) con y sin endotelio.
- Los anillos se contrajeron y se expusieron a concentraciones crecientes de protamina.
- Se evaluó el efecto de la NG-monometil-L-arginina (L-NMMA), un inhibidor de EDRF, y la L-arginina.
Principales resultados:
- La protamina indujo una relajación dependiente de la concentración en segmentos arteriales con endotelio.
- Esta relajación fue significativamente mayor que en los segmentos sin endotelio.
- La relajación mediada por EDRF fue inhibida por L-NMMA y revertida por L-arginina.
Conclusiones:
- La protamina estimula la liberación de EDRF desde el endotelio arterial.
- La vasodilatación dependiente del endotelio es un factor significativo en la hipotensión sistémica inducida por la protamina.
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