Figure 2.

Concentration response curves of aqueous-ethanolic extract from R. damascena and isoprenaline, on heart contractility of guinea pigs in group 1 (in the presence and absence of propranolol), (a for the isoprenaline and b for the extract), group 2 experiments (in the presence and absence of methacholine), (c for the isoprenaline and d for the extract) and group 3 (in the presence diltiazem), (e for the extract). Statistical differences between the the data in the presence and absence of propranolol and methacholie; NS: non-significant difference, *; p < 0.05, **; p < 0.01. Statistical differences between the data of each concentration of extract or isoprenaline compared to baseline value; +; p < 0.05, ++; p < 0.01, +++; p < 0.001. (n = 12 for each group).