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Los anticuerpos de pacientes preeclampticos estimulan el aumento de la movilización intracelular de Ca2+ a través de
Theingi M Thway1, Sergiy G Shlykov, Mary-Clare Day
1Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
Circulation
|September 24, 2004
Resumen
Los anticuerpos maternos dirigidos a los receptores de angiotensina II tipo I (AT1) activan estos receptores, aumentando los niveles intracelulares de calcio en pacientes con preeclampsia. Este hallazgo vincula los anticuerpos agonistas del receptor AT1 (AT1-AAs) con los cambios celulares observados en la preeclampsia.
Área de la Ciencia:
- Obstetricia y Ginecología.
- Inmunología Inmunología.
- Fisiología cardiovascular fisiología cardiovascular.
Sus antecedentes:
- La preeclampsia es un trastorno del embarazo marcado por hipertensión y anomalías vasculares.
- Los cambios celulares en la preeclampsia incluyen un aumento del calcio intracelular.
- Los anticuerpos contra los receptores de angiotensina II tipo I (AT1) están relacionados con la preeclampsia.
Objetivo del estudio:
- Para investigar si los anticuerpos agonistas del receptor AT1 (AT1-AAs) activan los receptores AT1.
- Para determinar si los AT1-AAs aumentan el calcio intracelular y activan las vías de señalización aguas abajo.
Principales métodos:
- Se examinó la IgG de 30 pacientes embarazadas (16 preeclamptic, 14 normotensivo) para la capacidad de movilizar el calcio intracelular.
- Bloqueo probado de la actividad AT1-AA utilizando losartan y un antagonista peptídico específico.
- Activación evaluada del factor nuclear de las células T activadas (NFAT) después de la estimulación AT1-AA.
Principales resultados:
- La IgG de todos los pacientes preeclampticos activó los receptores AT1 y aumentó el calcio libre intracelular.
- Ninguno de los individuos normotensos tenía IgG activada en los receptores AT1.
- La movilización de calcio inducida por AT1-AA fue bloqueada por losartán y un antagonista peptídico, y activó NFAT.
Conclusiones:
- Las AT1-AAs maternas activan los receptores AT1, lo que lleva a un aumento del calcio intracelular.
- Es probable que estos anticuerpos contribuyan a los cambios celulares y las alteraciones de la expresión génica en la preeclampsia.
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