Figure 4
From: Myocardial contractility is preserved early but reduced late after ovariectomy in young female rats
Lusitropic response to calcium and isoproterenol. Effect of ovariectomy on maximal and minimal rate of change in force in left ventricle papillary muscles isolated from sham operation (Sham) and ovariectomized (Ovx) rats at 60 days. A - Maximum and minimum dF/dt in increasing extracellular calcium concentrations from 0.62 to 3.75 mM. B- Effect of the β-adrenergic agonist isoproterenol in increasing concentrations from 10-8 to 10-2 M in isolated left ventricle papillary muscles from sham operation (Sham) and ovariectomized (Ovx) rats. Extracellular Ca2+ concentration was 0.62 mM. Force (g/g) values are expressed as mean ± S.E.M. *different from sham (P < 0.05) using two-way ANOVA and post hoc Tukey test. Number of animals used is indicated.