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ATPasa de calcio del retículo sarcoplasmático cardíaco, un antígeno autoinmune en la cardiomiopatía experimental
A R Sharaf1, J Narula, P D Nicol
1Al-Azhar University, Cairo, Egypt.
Circulation
|March 1, 1994
Resumen
La miocarditis autoinmune puede ser inducida al dirigirse a la ATPasa de calcio del retículo sarcoplásmico (SR-ATPasa). La inmunización con SR-ATPasa o sus anticuerpos conduce a daño cardíaco y miocarditis al interrumpir la regulación del calcio en las células del músculo cardíaco.
Área de la Ciencia:
- Cardiología Cardiología.
- Inmunología Inmunología.
- Patología Patología Patología.
Sus antecedentes:
- La miocarditis autoinmune está relacionada con varios antígenos miocárdicos.
- La sobrecarga sarcoplasmática de calcio es un factor conocido en la cardiomiopatía.
- Existe un vínculo potencial entre la regulación alterada del calcio en el sarcoplasma y la patogénesis de la miocarditis.
Objetivo del estudio:
- Investigar si la inmunización con ATPasa de calcio del retículo sarcoplásmico (SR-ATPasa) o anticuerpos contra ella puede inducir cardiomiopatía y miocarditis.
- Explorar el papel de la SR-ATPasa en la regulación del calcio intracelular y la contractilidad miocárdica.
Principales métodos:
- Generó un anticuerpo monoclonal (4C11-20.21) contra la SR-ATPasa cardíaca canina.
- Se inyectan proteínas purificadas de SR-ATPasa o células de hibridoma que producen el anticuerpo en ratones.
- Se evaluaron las lesiones miocárdicas, la degeneración de los miocitos y la localización de anticuerpos mediante histología y microscopía.
Principales resultados:
- Los ratones inmunizados con la proteína SR-ATPase desarrollaron lesiones miocárdicas y miocarditis con el tiempo.
- Los ratones inyectados con el anticuerpo 4C11-20.21 mostraron degeneración de los miocitos cardíacos sin infiltración celular.
- Anticorpo localizado en el sistema miotubular subsarcolemal y el sarcolema adyacente, con deposición del complemento en los miocitos cardíacos.
Conclusiones:
- La SR-ATPasa cardíaca actúa como un autoinmunógeno capaz de inducir una miocarditis autoinmune.
- Los anticuerpos contra la SR-ATPasa cardíaca inhiben los procesos miocárdicos dependientes de la energía.
- Es probable que la mionecrosis observada se deba a una interferencia con la regulación del calcio, lo que afecta la contractilidad miocárdica.
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