摘要Objective:To investigate the analgesic substances in the aerial part of Urtica fissa(Urticae Fissae Herba),commonly used for rheumatoid and rheumatism arthritis.Methods:The analgesic constituents were isolated with the active guidance of hot plate and acetic acid writhing models,and identified by comprehensive spectroscopic analysis.Results:Thirteen alkaloids(1-13),two lignans(14,15),and three amides(16-18)were isolated from the active fractions.Among them,compound 1 was a new alkaloid,and compound 6 was a new natural prod-uct.The activity evaluation in vivo indicated that various pyrrole alkaloids(1,3,6,and 12)possessed sig-nificant analgesic activities,they could significantly inhibit the mice pain response induced by acetic acid and hot plate at the dosage of 2 mg/kg BW.Conclusion:The study revealed that the pyrrole alkaloids played important roles in the analgesic activi-ties of Urticae Fissae Herba.