the involvement of non opioidergic mechanism in the antinociceptive and antilocomotive activity of bacopa monnieri

a hydroethanolic extract (he-ext) of bacopa monnieri (bm) was studied for antinociceptive effect in the animal models of acetic-acid-induced writhing test and antilocomotive effect in mice. standard centrally-acting analgesic, morphine (mp), and peripherally-acting one, diclofenac (diclo), were also tested along with the extract for comparison. the extract exhibited significant antinociceptive effect ( p < 0.001) in this test, not antagonized by the opioid receptor antagonist, naloxone (nlx) in a fashion similar to diclofenac. this excluded the involvement of opioids in the mediation of antinociceptive response of bacopa monnieri . moreover, the bm he-ext exhibited highly significant antilocomotive ( p < 0.0001) that was also unaffected by naloxone. these results indicate that bacopa monnieri possesses antinociceptive and antilocomotive effect that may be mediated through non-opioidergic mechanism.