Antinociceptive pattern of flavone and its mechanism as tested by formalin assay.

Flavone, dextrose and long swim stress exhibited antinociception. Degree of antinociception was grealer wilh long swim stress as compared to flavone or dextrose. Combination of these treatments resulted in potentiation of anlinociceptinn. Naloxone (opioid antagonist; 5 mg/kg ip) antagonised t1avone or long stress induced antinociception showing orioid mediated mechanism, however, failed to reverse the potentiated antinociceptive component recorded in long stressed animals which received t1avone and dextrose. Antinociceptive activity of tlavone, dextrose and long swim stress which was documented by acetic acid assay has been contirmed in the present study. Role for opioid system in this action has heen demonstrated. Therefore, formalin test can also be considered as an useful assay procedure for testing llavonoids. However. like acetic acid assay this assay procedure also has the limitation that it is unable to detect minor changes in the dqrrce of antinociception produced by physiological interventions such as long swim and dextrose.