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A Flow Cytometry-based Assay for Measuring Mitochondrial Membrane Potential in Cardiac Myocytes After Hypoxia/Reoxygenation
Published on: July 13, 2018
La testosterona induce la citoprotección mediante la activación de los canales K + sensibles al ATP en la membrana
Fikret Er1, Guido Michels, Natig Gassanov
1Department of Internal Medicine III, University of Cologne, Cologne, Germany.
Circulation
|November 3, 2004
Resumen
La testosterona protege las células cardíacas del daño mediante la activación de los canales de potasio mitocondriales sensibles al ATP (mitoKATP). Este hallazgo sugiere que la testosterona puede ayudar a la recuperación después de un ataque al corazón.
Área de la Ciencia:
- Ciencias Cardiovasculares Ciencias Cardiovasculares
- Endocrinología Endocrinología.
- Fisiología celular Fisiología celular.
Sus antecedentes:
- Los andrógenos se han relacionado históricamente con efectos cardiovasculares adversos.
- La evidencia emergente sugiere que la testosterona puede beneficiar la recuperación del miocardio después de la isquemia / reperfusión.
- El papel de los canales de potasio sensibles al ATP en los efectos cardioprotectores de la testosterona requiere una aclaración.
Objetivo del estudio:
- Para investigar si la testosterona mejora la tolerancia miocárdica a la isquemia.
- Para determinar si este efecto está mediado por los canales mitocondriales (mitoKATP) o sarcoplasmáticos (sarcKATP) de KATP.
Principales métodos:
- Utilizó un modelo celular de isquemia para evaluar la muerte de los cardiomiocitos.
- Se midió la fluorescencia de la flavoproteína mitocondrial para indexar la actividad de mitoKATP.
- Realizó experimentos con pinzas para evaluar la función del canal KATP en miocitos intactos y mitoplastos aislados.
Principales resultados:
- La testosterona redujo significativamente la muerte de los cardiomiocitos inducida por isquemia, un efecto bloqueado por el ácido 5-hidroxidecanoico (un inhibidor de mitoKATP).
- La testosterona aumentó la fluorescencia de la flavoproteína mitocondrial, lo que indica la activación de mitoKATP, que era dependiente de K+ y sensible al ATP.
- La activación directa de los canales KATP de la membrana mitocondrial interna por la testosterona se observó en grabaciones de un solo canal; no se encontró ningún efecto en los canales sarcKATP.
Conclusiones:
- Proporcionó evidencia directa de los canales mitoKATP cardíacos.
- Se estableció un vínculo entre la citoprotección inducida por la testosterona y la activación del canal mitoKATP.
- Sugiere que la testosterona endógena puede desempeñar un papel importante en la recuperación después del infarto de miocardio.
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