The effects of endothelin-1 on myocardial function [Efeitos da endotelina-1 sobre a função miocárdica.]

• Type: Article in International Scientific Journal
• Date: 2000

Authors

Leite-Moreira AF (Author) FMUP; Rocha-Sousa A (Author) FMUP; Henriques-Coelho, T (Author) FMUP; Roncon Alburqueque Junior, R (Author) Other; Castro-Chaves P (Author) FMDUP

Journal

Title: Revista Portuguesa de Cardiologia

Vol. 19 No. 3

Pages: 79-83

ISSN: 0870-2551

Publisher: Sociedade Portuguesa De Cardiologia

Indexing

Scopus - 1 Citation

Other information

Authenticus ID: P-008-PNF

Abstract (EN): INTRODUCTION: Endothelin-1 (ET-1) has potent vasoconstrictor, growth promoting and positive inotropic properties, with increased plasma levels in heart failure (HF). With regard to the cardiac effects of ET-1, most studies have not been able to differentiate its effects on the intrinsic properties of the myocardium from the secondary effects resulting from load changes and coronary vasoconstriction. This study investigated the myocardial effects of ET-1. METHODS: The study was performed on isolated rabbit papillary muscles (n = 9), before and after the addition of ET-1 (10 nM) to the superfusing solution (Krebs-Ringer; 1.25 nM Ca2+; 35 degrees C). One isotonic, one isometric and two afterloaded-isotonic twitches were recorded and analyzed. Only significant results (mean +/- SE, p < 0.05) are given, expressed as delta % baseline. RESULTS: ET-1 induced an increase of AT (147 +/- 33%), dT/dtmax (154 +/- 39%) and dT/dtmin (145 +/- 38%), while the duration of the twitch did not vary significantly. In addition, after ET-1, RT at the end of the isometric twitch decreased by 19 +/- 3%, when compared with the control and to its value at the beginning of the twitch. CONCLUSIONS: This study showed that, in addition to the well-known positive inotropic effect, ET-1 improves diastolic function by accelerating relaxation rate (dT/dtmin) and decreasing RT. These results may have important implications in the pathophysiology of HF.

Language: Portuguese

Type (Professor's evaluation): Scientific