title: Small concentrations of mercury enhances positive inotropic effects in the rat ventricular myocardium.
abstract: Small concentrations of mercury reduce the force development of the rat right myocardium and inhibit the sodium pump. This inhibition might increase the amount of activator Ca(2+) in the sarcoplasmic reticulum available upon activation. We further investigated whether this action could potentiate positive inotropic effects produced by Ca(2+) increment (0.62-1.25mM) and isoproterenol (20nM). Right ventricular strips contracting isometrically were treated with 0.1 and 1μM HgCl(2). Results showed that after HgCl(2) treatment the magnitude of both inotropic interventions was increased. Considering that Hg(2+) amongst its effects induces hypertension and might be associated with cardiovascular diseases these potentiating effects might have hazardous consequences.
authors.affiliation: Departments of Physiological Sciences, CBM/UFES, Av. Marechal Campos 1468, 29040-090 Vitória, ES, Brazil.
authors.forename: Diego
authors.initials: D
authors.lastname: Falcochio
authors.forename: Gabriela Poltronieri Souza de
authors.initials: GP
authors.lastname: Assis
authors.forename: Ivanita
authors.initials: I
authors.lastname: Stefanon
authors.forename: Dalton Valentim
authors.initials: DV
authors.lastname: Vassallo