Abstract
Background Some studies show that some Dibenzo derivatives can produce
changes in the cardiovascular system; however, its molecular mechanism is not
very clear.
Objective The objective of this investigation was to evaluate the
inotropic activity of ten Dibenzo derivatives (compounds 1 to 10) on either
perfusion pressure or left ventricular pressure.
Methods Biological activity produced by the Dibenzo derivatives on either
perfusion pressure or coronary resistance was evaluated using an isolated rat
heart. In addition, the molecular mechanism of biological activity produced by
compound 4 (Dibenzo[b,e]thiophene-11(6H)-one) on left ventricular pressure was
determined using both Bay-k8644 and nifedipine as pharmacological tools in an
isolated rat heart model.
Results The results showed that Dibenzo[b,e]thiophene-11(6H)-one increases
perfusion pressure and coronary resistance at a dose of 0.001 nM.
Besides, other data display that Dibenzo[b,e]thiophene-11(6H)-one increases left
ventricular pressure in a dose-dependent manner (0.001 to 100 nM) and
this effect was similar to biological activity produced by Bay-k8644 drug on
left ventricular pressure. However, the effect exerted by
Dibenzo[b,e]thiophene-11(6H)-one was inhibited in the presence of nifedipine at
a dose of 1 nM.
Conclusions All these data suggest that Dibenzo[b,e]thiophene-11(6H)-one
increase left ventricular pressure through calcium channel activation. In this
way, Dibenzo[b,e]thiophene-11(6H)-one could be a good candidate as positive
inotropic agent to heart failure.
Key words
Dibenzo - derivative - calcium - channel