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Updated: Aug 12, 2026
13:32
Videomorphometric Analysis of Hypoxic Pulmonary Vasoconstriction of Intra-pulmonary Arteries Using Murine Precision Cut Lung Slices
Published on: January 14, 2014
¿La vasodilatación pulmonar normóxica en lugar de la vasoconstricción hipóxica explica la respuesta del presor
Lancet (London, England)
|March 4, 1978
Resumen
La hipoxia desencadena la hipertensión pulmonar al reducir la bradicinina, un vasodilatador. La inhibición de la inactivación de la bradicinina impide esta respuesta, lo que sugiere que la bradicinina tiene un efecto inhibidor.
Área de la Ciencia:
- Circulación pulmonar La circulación pulmonar es la circulación de los pulmones.
- Fisiología Vascular Fisiología Vascular
- Investigación de la hipoxia Investigación de la hipoxia.
Sus antecedentes:
- El mediador de la respuesta del presor pulmonar a la hipoxia sigue sin ser identificado.
- La vasodilatación pulmonar durante la normoxia puede mantenerse mediante vasodilatadores como la bradicinina.
- La bradicinina se libera en la ventilación pulmonar con aire u oxígeno, pero se inactiva rápidamente.
Objetivo del estudio:
- Para investigar el papel de la bradicinina en la respuesta del presor pulmonar a la hipoxia.
- Explorar el mecanismo por el cual la bradicinina influye en el tono vascular pulmonar.
- Para determinar si la inhibición de la inactivación de la bradicinina afecta a la hipertensión pulmonar inducida por hipoxia.
Principales métodos:
- Investigó la liberación y inactivación de bradicinina en los pulmones.
- Se examinó el efecto de la inhibición de la enzima inactivadora de la bradicinina en la hipertensión pulmonar.
- Se evaluó la formación de bradicinina en la sangre, los macrófagos alveolares y los granulocitos.
- Estudió la influencia de la tensión de oxígeno y el pH en el metabolismo de la bradicinina.
Principales resultados:
- La inhibición de la enzima que inactiva la bradicinina previene la hipertensión pulmonar durante la hipoxia crónica.
- La formación de bradicinina por los granulocitos es dependiente de la tensión de oxígeno.
- La enzima inactivadora de bradicinina también convierte la angiotensina I en angiotensina II.
- La tasa de inactivación de la bradicinina es sensible a los cambios en el pH.
Conclusiones:
- La reducción de la producción de bradicinina durante la hipoxia puede conducir a hipertensión pulmonar.
- La bradicinina juega un papel crucial en el mantenimiento del tono vascular pulmonar.
- Las interacciones entre los sistemas de bradicinina y angiotensina influyen en las circulaciones pulmonar y sistémica.
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