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Efectos cardíacos de la relaxina en ratas
H Kakouris1, L W Eddie, R J Summers
1Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Australia.
Lancet (London, England)
|May 2, 1992
Resumen
La relaxina humana sintética (hRlx-2) aumenta significativamente la frecuencia cardíaca y la contractilidad en las aurículas de la rata. Esta hormona exhibe potentes efectos cardíacos, probablemente actuando directamente en receptores específicos de relaxina en el corazón.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Endocrinología Endocrinología.
Sus antecedentes:
- Relaxin es principalmente conocida como una hormona del embarazo.
- La relaxina porcina ha demostrado efectos cardíacos, específicamente el aumento de la frecuencia cardíaca en ratas.
Objetivo del estudio:
- Para investigar los efectos cardíacos de la relaxina sintética del gen-2 humano (hRlx-2).
- Para determinar los efectos cronotrópicos e inotrópicos de hRlx-2 en las aurículas de ratas aisladas.
Principales métodos:
- Utilizado en experimentos in vitro con las aurículas de ratas aisladas.
- Evaluación de los efectos dependientes de la concentración de hRlx-2 sintético en la función cardíaca.
Principales resultados:
- El hRlx-2 sintético demostró efectos cronotrópicos positivos dependientes de la concentración en el latido espontáneo de la aurícula derecha (EC50 = 0,09 nmol/l).
- El hRlx-2 sintético exhibió efectos inotrópicos positivos dependientes de la concentración en las aurículas izquierdas impulsadas eléctricamente (EC50 = 0,31 nmol/l).
- La potencia de hRlx-2 excedió la de la endotelina, la angiotensina II y la (-) -isoprenalina en las aurículas de ratas.
Conclusiones:
- La relaxina humana (hRlx-2) posee potentes efectos positivos cronotrópicos e inotrópicos en el corazón.
- Es probable que estos efectos cardíacos estén mediados a través de la acción directa sobre los receptores de relaxina.
- El papel de Relaxin puede extenderse más allá del embarazo para dirigir la modulación cardíaca.
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