Antinociceptive activity of Ligusticum porteri preparations and compounds.

BACKGROUND

The roots and rhizomes of Ligusticum porteri Coulter & Rose (Apiaceae) are widely used in Mexican folk medicine for several purposes, including painful complaints.

OBJECTIVE

The main goal of this work was to demonstrate the analgesic action in mice of some preparations and major compounds from L. porteri.

METHODS

The extracts, aqueous (AE) and organic (OE), the essential oil (EO) and major compounds (10-316 mg/kg) from L. porteri were evaluated as potential antinociceptive agents using the acetic acid-induced writhing and hot plate tests in ICR mice.

RESULTS

All preparations tested exhibited significant antinociceptive effect in the two animal pain models selected. AE and EO were more effective in the writhing test while OE had a better effect in the hot-plate model. On the other hand, Z-ligustilide (1) provoked an increment in the latency period to the thermal stimuli in the hot-plate test at a dose of 31.6 mg/kg, and a decrease in the number of abdominal writhes at 10 mg/kg. Z-3-butylidenephthalide (2) induced a dose-dependent antinociceptive action in the hot-plate assay; this compound was also effective for controlling the pain provoked by chemical irritation at the doses of 10 and 31.6 mg/kg. Finally, diligustilide (3) inhibited the number of writhing responses at all doses tested but was inactive in the hot-plate model.

CONCLUSIONS

The present investigation provides in vivo evidence supporting the use of L. porteri to treat painful conditions in folk medicine.