title: Mechanisms underlying the antispasmodic and bronchodilatory properties of Terminalia bellerica fruit.
abstract: OBJECTIVE
  The present investigation was carried out to provide the pharmacological basis for the medicinal use of Terminalia bellerica in hyperactive gastrointestinal and respiratory disorders.
  
  
  METHODS
  Crude extract of Terminalia bellerica fruit (Tb.Cr) was studied in in vitro and in vivo.
  
  
  RESULTS
  Tb.Cr caused relaxation of spontaneous contractions in isolated rabbit jejunum at 0.1-3.0mg/mL. Tb.Cr inhibited the carbachol (CCh, 1microM) and K(+) (80mM)-induced contractions in a pattern similar to that of dicyclomine, but different from nifedipine and atropine. Tb.Cr shifted the Ca(++) concentration-response curves to right, like nifedipine and dicyclomine. In guinea-pig ileum, Tb.Cr produced rightward parallel shift of acetylcholine-curves, followed by non-parallel shift at higher concentration with the suppression of maximum response, similar to dicyclomine, but different from nifedipine and atropine. Tb.Cr exhibited protective effect against castor oil-induced diarrhea and carbachol-mediated bronchoconstriction in rodents. In guinea-pig trachea, Tb.Cr relaxed the CCh-induced contractions, shifted CCh-curves to right and inhibited the contractions of K(+). Anticholinergic effect was distributed both in organic and aqueous fractions, while CCB was present in the aqueous fraction.
  
  
  CONCLUSIONS
  These results indicate that Terminalia bellerica fruit possess a combination of anticholinergic and Ca(++) antagonist effects, which explain its folkloric use in the colic, diarrhea and asthma.
authors.affiliation: Department of Biological and Biomedical Sciences, The Aga Khan University Medical College, Karachi 74800, Pakistan. anwar.gilani@aku.edu
authors.forename: Anwarul Hassan
authors.initials: AH
authors.lastname: Gilani
authors.forename: Arif-Ullah
authors.initials: AU
authors.lastname: Khan
authors.forename: Tuba
authors.initials: T
authors.lastname: Ali
authors.forename: Saad
authors.initials: S
authors.lastname: Ajmal
mesh_terms: D000818:Animals; D001993:Bronchodilator Agents / Q000494:pharmacology*; D005260:Female; D005638:Fruit / Q000737:chemistry; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects*; D007583:Jejunum / Q000187:drug effects*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010276:Parasympatholytics / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology* / Q000633:toxicity; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D029766:Terminalia / Q000737:chemistry*; D014132:Trachea / Q000187:drug effects*
chemical_list: D001993:Bronchodilator Agents; D010276:Parasympatholytics; D010936:Plant Extracts