Antinociceptive activity of the essential oil and fractions of pterodon emarginatus vogel seeds

In the present study the antinociceptive property of Pterodon emarginatus Vog. (Leguminosae) seeds essential oil (EO) and fractions was investigated. The writhing test induced by acetic acid, paw licking induced by formalin and hot plate tests were performed in Swiss albino mice (n = 8-10/group), by oral route at doses of 100, 300 and 500 mg/kg. The EO, hexanic (HF) and buthanolic (BF) fractions reduced (p < 0.01) the abdominal contortions (100 mg/kg = 22.75 ± 4.03, 14.38 ± 3.41 and 24.6 ± 4.48; 300 mg/kg = 14.00 ± 5.81, 12.13 ± 3.19, and 25.88 ± 2.78; 500 mg/kg = 11.13 ± 3.59, 9.00 ± 2.09 and 17.75 ± 4.82), respectively when compared with control group. The EO and methanolic fraction (MF) reduced the paw licking in both phases (p<0.05): 1st phase (100 mg/kg = 31.63 ± 14.17 and 60.50 ± 11.61; 300 mg/kg = 28.38 ± 5.72 and 47.75 ± 6.13; 500 mg/kg = 28,25 ± 4.19 and 44.63 ± 6.33) and 2nd phase (100 mg/kg = 53.50 ± 11.96 and 24.13 ± 12.38; 300 mg/kg = 43.75 ± 11.91 and 35.13 ± 12.35; 500 mg/kg = 9.00 ± 4.41 and 23.50 ± 10.18), respectively. Only HF showed effect on the reaction time at hot plate were significant (p<0.05) after 60 min of treatment. These results suggest that Pterodon emarginatus could constitute a source of active substances with antinociceptive effect. Colegio de Farmacéuticos de la Provincia de Buenos Aires