title: Chemical analysis and calcium channel blocking activity of the essential oil of Perovskia abrotanoides.
abstract: The aim of this study was to investigate the chemical composition and provide a pharmacological base for the medicinal use of the essential oil of Perovskia abrotanoides (Pa.Oil) in gastrointestinal disorders, such as colic. The chemical investigation resulted in the identification of 26 compounds, of which tricyclene, beta-trans-ocimene, terpinene-4-acetate, terpinen-4-ol, caran-3beta-ol, linalyl acetate, beta-caryophyllene oxide and alpha-elemene had not previously been reported from P. abrotanoides. Major constituents were 1,8-cineol and delta-3-carene, which constituting 50% of the oil. In the isolated rabbit jejunum preparation Pa.Oil caused inhibition of spontaneous and high K+ (80 mM)-induced contractions, with respective EC50 values of 0.13 (0.08-0.20; n = 4) and 0.90 mg/mL (0.50-1.60; n = 5), thus showing that spasmolytic activity is mediated possibly through calcium channel blockade (CCB). The CCB activity was confirmed when pre-treatment of the tissue with Pa.Oil (0.03-0.1 mg/mL) caused a rightward shift in the Ca++ concentration-response curves, similar to that caused by verapamil, a standard calcium channel blocker. These data indicate that the essential oil of P. abrotanoides possesses spasmolytic activity mediated possibly through inhibition of voltage-dependent calcium channels, which may explain its medicinal use in colic and possibly diarrhea.
authors.affiliation: Natural Products Research Unit, Department of Biological and Biomedical Sciences, Aga Khan University Medical College, Karachi-74800, Pakistan.
authors.forename: Abdul Jabbar
authors.initials: AJ
authors.lastname: Shah
authors.affiliation: Department of Chemistry, University of Karachi, Karachi 75270, Pakistan.
authors.forename: Munawwer
authors.initials: M
authors.lastname: Rasheed
authors.affiliation: Natural Products Research Unit, Department of Biological and Biomedical Sciences, Aga Khan University Medical College, Karachi-74800, Pakistan.
authors.forename: Qaiser
authors.initials: Q
authors.lastname: Jabeen
authors.affiliation: Pakistan Council of Scientific and Industrial Research Laboratory, Karachi-75280, Pakistan.
authors.forename: Amir
authors.initials: A
authors.lastname: Ahmed
authors.affiliation: Department of Botany, University of Baluchistan, Quetta, Pakistan.
authors.forename: Rasool Bakhsh
authors.initials: RB
authors.lastname: Tareen
authors.affiliation: Natural Products Research Unit, Department of Biological and Biomedical Sciences, Aga Khan University Medical College, Karachi-74800, Pakistan.
authors.forename: Anwarul Hassan
authors.initials: AH
authors.lastname: Gilani
authors.affiliation: Department of Chemistry, University of Karachi, Karachi 75270, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Nadir
authors.affiliation: H.E.J. Research Institute of Chemistry, ICCBS, University of Karachi, Karachi-75270, Pakistan.
authors.forename: Viqar Uddin
authors.initials: VU
authors.lastname: Ahmad
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D019686:Lamiaceae / Q000737:chemistry*; D008297:Male; D009822:Oils, Volatile / Q000032:analysis* / Q000494:pharmacology; D011817:Rabbits
chemical_list: D002121:Calcium Channel Blockers; D009822:Oils, Volatile; D002118:Calcium