title: Inhibitory effect of Zataria multiflora Boiss and carvacrol on histamine (H(1) ) receptors of guinea-pig tracheal chains.
abstract: The inhibitory effect of aqueous-ethanolic extract of Zataria multiflora Boiss (Labiatae) and carvacrol on histamine (H(1) ) receptors was examined on tracheal chains of guinea-pigs. The effects of three concentrations of aqueous-ethanolic extract, carvacrol, 10 nm chlorpheniramine, and saline on histamine (H(1) ) receptors were tested on three groups of guinea-pig tracheal chains as follows: incubated trachea with (i) indomethacin (n = 9), (ii) indomethacin, propranolol, and atropine (n = 7), and (iii) indomethacin and propranolol (n = 6). The EC(50) (effective concentration of histamine causing 50% of maximum response) obtained in the presence of chlorpheniramine for all concentrations of the extract and carvacrol in all three groups was significantly higher than that of saline (P < 0.001 for all cases). The EC(50) obtained in the presence of all concentrations of extract in groups 2 and 3 was lower than group 1 and in group 3 lower than group 2 (P < 0.01 to P < 0.001). However, EC(50) obtained in the presence of all concentrations of carvacrol in group 3 and two higher concentrations in group 2 was higher than that of group 1 (P < 0.01 to P < 0.001). There was no significant difference in the maximum response obtained in the presence of different concentrations of extract and carvacrol between three groups. There was a parallel rightward shift in concentration-response curves obtained in the presence of all concentrations of the extract and carvacrol in all three groups. These results indicated an inhibitory effect of Z. multiflora and its constituent carvacrol on histamine H(1) receptors.
authors.affiliation: Department of Physiology and Pharmaceutical Research Centre, Medical School, Mashhad University of Medical Sciences, Mashhad, Iran. boskabadymh@mums.ac.ir
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Boskabady
authors.forename: Hengameh
authors.initials: H
authors.lastname: Tabanfar
authors.forename: Zahra
authors.initials: Z
authors.lastname: Gholamnezhad
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Sadeghnia
mesh_terms: D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002744:Chlorpheniramine / Q000494:pharmacology; D000081007:Cymenes; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D006632:Histamine / Q000378:metabolism; D006634:Histamine H1 Antagonists / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D007213:Indomethacin / Q000494:pharmacology; D019686:Lamiaceae / Q000737:chemistry*; D008297:Male; D039821:Monoterpenes / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D011969:Receptors, Histamine H1 / Q000187:drug effects / Q000378:metabolism; D014132:Trachea / Q000187:drug effects / Q000378:metabolism
chemical_list: D000081007:Cymenes; D006634:Histamine H1 Antagonists; D039821:Monoterpenes; D010936:Plant Extracts; D011969:Receptors, Histamine H1; D002744:Chlorpheniramine; D001285:Atropine; D006632:Histamine; C073316:carvacrol; D011433:Propranolol; D007213:Indomethacin