In the present work the effect of
dioclein, a new
flavonoid from Dioclea grandiflora, was investigated in rat hearts. The experiments were performed using the classic method of Langendorff, where flow, inotropic, chronotropic and electric parameters were analyzed. Bolus administration of
Dioclein (1-100 microg) induced a sustained and dose-dependent increase in coronary flow with no modification in inotropic, chronotropic and electrical parameters. The duration of increase in coronary flow induced by
dioclein (10 microg) was approximately 4-fold higher than that observed in the presence of
sodium nitroprusside (NPS; 10 microg). Besides, the effect of
dioclein measured as the area-under-the-curve was approximately 4.5-folds higher than that observed with NPS. Pre-treatment with
L-NAME (100 microM) and
indomethacin (10 microM) alone did not modify the effect of
dioclein (10 microg), suggesting that
nitric oxide (NO) and
cyclooxygenase-derived factors were not involved. However, association of
L-NAME plus
indomethacin inhibited the duration of the effect of
dioclein (10 microg) without changing its increase in the coronary flow. Furthermore, the absence of alteration in inotropism and chronotropism of the heart associated with its coronary effect suggest that
dioclein could be an interesting lead compound for the development of drugs for the treatment
coronary heart diseases.