Antinociceptive activity of 1-nitro-2-phenylethane, the main component of Aniba canelilla essential oil.

Aniba canelilla (H.B.K.) Mez is a medicinal plant used in the Amazon folk therapeutic as antispasmodic, antidiarreic, carminative, tonic agent and a stimulant of the digestive and central nervous system. Our preliminary studies showed that the plant essential oil has analgesic activity in mice. Now, we are reporting the antinociceptive effect of the compound 1-nitro-2-phenylethane (97.5%), the main component of the essential oil of Aniba canelilla, which was obtained by column chromatographic purification. In the writhing test this compound was dosed at 15, 25 and 50 mg/kg reducing the abdominal writhes in a significant manner; in the hot plate test it was assayed at 50, 100 and 200 mg/kg producing no alterations in the latency time when compared to the control; and in the formalin test the 1-nitro-2-phenylethane was tested at 50 and 25 mg/kg decreasing significantly the second phase of the algic stimulus. The study suggests that the 1-nitro-2-phenylethane has analgesic activity, probably of peripheral origin. The mechanism involved is not completely understood, however, the results suggest that the opioid receptors are involved in the antinociceptive action observed to 1-nitro-phenylethane.