ABSTRACT
Objective: The aim of this study was to evaluate the antinociceptive activity of the methanol extract of Tabebuia hypoleuca stems [THME]
Materials and Methods: The animals were divided into 5 groups of 8 mice for each test [negative controls, positive controls, and 3 groups treated with THME at doses of 150, 300, and 500 mg/kg, p.o.]
The antinociceptive effect of THME was evaluated using the writhing, formalin, tail flick, and hot plate models in mice
Results: In the writhing test, THME [150,300, and 500 mg/kg] produced significantly [p < 0.001] fewer writhes induced by acetic acid than in the control group. In the formalin test, the licking time forTHMEat doses of 300and 500 mg/kg was significantly shorter [p < 0.001] compared to the control group in the first phase of the formalin test, whereas in the second phase only the dose of 500 mg/kg showed an antinociceptive effect. In addition, THME at doses of 300 and 500 mg/kg significantly increased the latency time in the tail flick test [p < 0.05 and p < 0.001, respectively] and in the hot plate test [p < 0.01 and p < 0.001, respectively] compared to the control group
Conclusions: These results show that THME had antinociceptive activity using several models of nociception, and they suggest that the effect is mediated by the participation of both peripheral and central antinociceptive mechanisms