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Endothelial Cell Tube Formation Assay for the In Vitro Study of Angiogenesis
Published on: September 1, 2014
La formación de angiotensina II dependiente de la quimasas en el tejido vascular humano
1Department of Pharmacology, Osaka Medical College, Takatsuki City, Osaka, Japan. Pha010@art.osaka-med.ac.jp
Circulation
|August 10, 1999
Resumen
La quimaza humana ligada a la heparina contribuye significativamente a la formación de angiotensina II, incluso con inhibidores naturales de la proteasa como la alfa-antitripsina presente. Esto pone de relieve su papel funcional in vivo.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Fisiología Fisiología Fisiología.
Sus antecedentes:
- Estudios previos sugirieron una contribución limitada in vitro de la quimasa cardíaca humana a la formación de angiotensina II en presencia de inhibidores de la proteasa.
- La relevancia in vivo de la actividad de la quimasa, en particular cuando se une a la heparina, sigue sin estar clara.
Objetivo del estudio:
- Investigar el papel de la quimaza humana unida a la heparina en la formación de angiotensina II.
- Para evaluar el impacto de los inhibidores naturales de la proteasa en este proceso.
Principales métodos:
- Utilizados extractos de tejido vascular humano que contienen angiotensina I.
- Se empleó cromatografía de afinidad de heparina para aislar la quimaza ligada a la heparina.
- Se evaluó la formación de angiotensina II y la inhibición por lisinopril, quimostatina y alfa-antitripsina.
Principales resultados:
- La quimaza ligada a la heparina demostró una actividad significativa de formación de angiotensina II.
- Esta actividad fue inhibida por la quimostatina y la alfa-antitripsina, lo que indica su papel funcional.
- La formación de angiotensina II fue dependiente del tiempo y aumentó en la fracción unida a la heparina.
Conclusiones:
- La quimaza humana unida a la heparina juega un papel funcional crucial en la formación de angiotensina II.
- Esta actividad persiste en presencia de inhibidores naturales de la proteasa como la alfa-antitripsina.
- Los hallazgos sugieren la importancia de la quimasa en la generación fisiológica de angiotensina II in vivo.
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