This study was designed to observe the effects of
MCI-154, a
calcium sensitizer, on cardiac dysfunction after endotoxic
shock in rabbits. Ten hours after the rabbits were given injection of 1.0 mg/kg
endotoxin (Escherichia coli, O111:B4) via marginal ear veins, 0.1 mg/kg
MCI-154 was injected intravenously and then 50 mL/kg
normal saline (NS) + 0.1 mg/kg
MCI-154 was infused continuously at a rate of 0.7 mL/min. During this process, the parameters of cardiac function were measured. It was found that 10 h after the
endotoxin injection, heart rate (HR) was increased significantly while the mean arterial blood pressure (MAP), left ventricular systolic pressure (LVSP), isovolumetric pressure (IP), myocardial contractility (MC), and the area of p-dp/dt(max) vector loop (Lo) all were markedly decreased. Treatment with 50 mL/kg NS alone had slight effects on these parameters. On the contrary, LVSP, IP, MC, and Lo all were increased significantly while HR was not obviously changed and left ventricular end-diastolic pressure (LVEDP) was reduced remarkably following
MCI-154 administration in endotoxic
shock rabbits. The parameters of myocardial contractility were improved nearly to the values in
sham shock group and were markedly higher than that in NS alone-treated group. It can be concluded that
MCI-154 can exert significant
therapeutic effects on cardiac dysfunction after endotoxic
shock, for it improves cardiac function, dilates peripheral blood vessels, and slightly affects HR.