Resumo

ALFONSO-PEREZ, Candelaria; LAMANNA, Vito  e  ORTIZ, Holger N. Cinética de la potenciación post-reposo en tiras de ventrículo derecho aislado de rata, después de varias maniobras inotrópicas. AVFT [online]. 2008, vol.27, n.1, pp.79-81. ISSN 0798-0264.

In this work, positive inotropics maneuvers (diminution of [Na⁺]e, [ K⁺]e and changes of the frequency), and negative inotropics maneuvers (diminution of [Ca²⁺]e and adition of ryanodine) were made in right ventricle strip of male anaesthesia rats, stimulated bipolar to 1 or 3 Hz. The maxim potentiation was to the 32 s, with monotonic diminution until the stable state. The diminution of [ Na⁺]e produced a positive inotropic effect ( p<0,05) up to 16 s rest. With of 64 s rest and 3 Hz, the force of contraction of the beats was smaller, perhaps by a greater activity of Na⁺/Ca²⁺ interchanger. The diminution of [ Ca²⁺]e produced a negative inotropic effect up to 16 s rest. The ryanodine was only inotropic maneuver that change kinetic of potentiation the post-rest and of the stable state, which indicates that the potentiation depend of the Ca²⁺ released of the sarcoplasmic reticulum.

Palavras-chave : cardiac tissues; potentiation post-rest; ryanodine; rat.