title: Dichrostachys cinerea (L.) Wight et Arn (Mimosaceae) hydro-alcoholic extract action on the contractility of tracheal smooth muscle isolated from guinea-pig.
abstract: BACKGROUND
  Dichrostachys cinerea (L.) Wight et Arn. (Mimosaceae) is largely used in ethno-medically across Africa, and mainly employed for the treatment of asthma in Ivory Coast and Gabon. The paper analyses the relaxation induced by the methanolic extract of D. cinerea (Edici) in the guinea-pig trachea preparations (GPTPs).
  
  
  OBJECTIVE
  This study aimed to bring out the scientific basis to the use of this plant leading to the validation of this phytomedicine.
  
  
  METHODS
  The aorta obtained from guinea-pigs was immediately placed in a Mac Ewen solution. Experiments were performed in preparations suspended between two L-shaped stainless steel hooks in a 10 ml organ bath containing Mac Ewen solution. The isometric contractile force of the aorta strips of guinea-pig were recorded by using a strain gauge. The different drugs were directly administered into the organ bath and the magnitude of GPTPs was evaluated.
  
  
  RESULTS
  Phytochemical analysis of the methanolic extract of Dichrostachys cinerea (Edici) using chemical methods revealed the presence of flavenoids, tannins, sterols, triterpenes and polyphenols. Pharmacological studies performed in GPTPs show that of Dichrostachys cinerea (0.1 mg/ml - 2 mg/ml) evoked a broncho-constriction in GPTPs. Whereas, at concentration up to 2 mg/ml, Edici induced a significant dose-dependent relaxation in the GPTPs. KCl-, ACh- or histamine-evoked contractions of isolated trachea was significantly inhibited by increasing concentrations of Edici (3.5-10 mg/ml). Edici (10 mg/ml) as well as promethazine (0.25 mg/ml) significantly inhibited contractions induced by increasing concentrations of histamine (1×10-7-1×10-4mg/ml). In the presence of atropine at a concentration of 10-6mg/ml, contractile response curve (CRC) evoked by ACh (1×10-5-1×10-2 mg/ml) was significantly abolished in concentration-dependent manner. Edici did not significantly reduced ACh evoked contraction (10-5-10-2mg/ml).
  
  
  CONCLUSIONS
  These observations suggest that Edici could act through two mechanisms: firstly by activation of β-adrenergic or histaminergic receptors; and secondly muscarinic receptors may not be greatly involved, that justifying the use of the extract in traditional Medicine in Africa.
authors.affiliation: Institut de Pharmacopée et de Médecine Traditionnelle, Centre National de la Recherche Scientifique et Technologique (Cenarest) BP: 1156 Route de Sibang 3 Libreville Gabon.
authors.forename: Raissa Rr
authors.initials: RR
authors.lastname: Aworet-Samseny
authors.forename: Alain
authors.initials: A
authors.lastname: Souza
authors.forename: Fidele
authors.initials: F
authors.lastname: Kpahé
authors.forename: Kiessoun
authors.initials: K
authors.lastname: Konaté
authors.forename: Jacques Y
authors.initials: JY
authors.lastname: Datté
mesh_terms: D000818:Animals; D001249:Asthma / Q000188:drug therapy*; D001285:Atropine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae / Q000737:chemistry*; D006168:Guinea Pigs; D006632:Histamine / Q000378:metabolism; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D016488:Medicine, African Traditional; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D010276:Parasympatholytics / Q000494:pharmacology* / Q000627:therapeutic use; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D011398:Promethazine / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects* / Q000502:physiology
chemical_list: D006634:Histamine H1 Antagonists; D010276:Parasympatholytics; D010936:Plant Extracts; D001285:Atropine; D006632:Histamine; D011398:Promethazine