title: Analgesic and anti-inflammatory activities of the aqueous stem and leaf extract of Asystasia gangetica (Linn) T. Anderson.
abstract: BACKGROUND
  Asystasia gangetica (Linn) T. Anderson [family Acanthaceae] is used commonly in the sub-tropics and tropics for the management of inflammatory and algesic conditions.
  
  
  OBJECTIVE
  The study was done to evaluate the analgesic and inflammatory activity of the aqueous stem and leaf extract of Asystasia gangetica.
  
  
  METHODS
  The analgesic effect of the aqueous stem and leaf extract of Asystasia gangetica (25, 50, 100 and 200 mg/kg) was evaluated in rats and mice using the acetic acid induced writhing, cold water tail flick and hot plate models. Its anti-inflammatory effect was evaluated using carrageenan induced rat paw oedema and xylene induced mouse ear oedema models.
  
  
  RESULTS
  The aqueous stem and leaf extract of Asystasia gangetica (25-200 mg/kg) significantly (p < 0.05) reduced the number of writhes in the acetic acid induced writhing test. At 100 mg/kg, it produced an increase in pain threshold comparable to that produced by morphine (10 mg/kg) in the tail flick test and peak analgesia at 200 mg/kg in the hot plate test. The extract (25-200 mg/kg) also produced significant (p < 0.05) inhibition of oedema comparable to indomethacin (10 mg/kg) in the carrageenan induced paw oedema model. The extract (200 mg/kg) produced a significant inhibitory effect (p < 0.05) comparable to that produced by 1 mg/kg dexamethasone in the xylene induced mouse ear oedema model. Preliminary phytochemical screening showed that the extract contains alkaloids, tannins, cardiac glycosides and flavonoids. It did not produce mortality or any visible sign of lethality 24 hours after single oral administration of 10 g/kg.
  
  
  CONCLUSIONS
  The results show that the aqueous stem and feaf extract of Asystasia gangetica possesses analgesic and antiinflammatory activities.
authors.affiliation: Department of Pharmacology, Faculty of Basic Medical Sciences, College of Medicine, University of Lagos, PMB 12003, Idiaraba, Surulere, Lagos, Nigeria. ooadey@yahoo.com
authors.forename: Olufunmilayo O
authors.initials: OO
authors.lastname: Adeyemi
authors.forename: Flora R
authors.initials: FR
authors.lastname: Aigbe
authors.forename: Noblefather G
authors.initials: NG
authors.lastname: Uyaiabasi
mesh_terms: D027901:Acanthaceae / Q000737:chemistry*; D019342:Acetic Acid / Q000008:administration & dosage / Q000633:toxicity; D000700:Analgesics / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D002351:Carrageenan / Q000009:adverse effects; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy*; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy*; D007928:Lethal Dose 50; D051379:Mice; D010147:Pain Measurement / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D014867:Water
chemical_list: D000700:Analgesics; D000893:Anti-Inflammatory Agents; D010936:Plant Extracts; D014867:Water; D002351:Carrageenan; D019342:Acetic Acid