title: Possible mechanism of cardiac depressant activity of Berberis orthobotrys roots in isolated rabbit heart.
abstract: Berberis orhob, otrvs Bien. ex Aitch. (B.o.) has been reported to have antihypertensive effect in different experimental models. The aim of present study was to evaluate the possible antihypertensive mechanism. Aqueous methanolic extract of B.o. roots and its various fractions namely (ethyl acetate, n-butanol or aqueous) in different concentrations (10 ng/mL, 100 ng/mL, I pg/mL, 10 pg/mL, 100 pg/mL ) were evaluated in isolated perfused rabbit heart to assess their effect on force of contraction, HR and perfusion pressure. The crude extract of B.o. and its fractions exhibited a significant decrease in heart rate, contractility and perfusion pressure of isolated rabbit heart, however, butanolic fraction produced more prominent effect and was selected for further study. The effects of butanol fraction were not blocked by atropine (10' M) in isolated perfused heart. However, butanol fraction significantly blocked the effects of adrenaline (10' M). It is therefore conceivable that cardiac depressant activity of B.o. butanol fraction might be due to the presence of certain 3-blocking agents which might be responsible for antihypertensive effect However, further experiments are required to isolate the active compound(s) and elucidate exact mechanism of action.
authors.lastname: Alamgeer
authors.forename: Muhammad Shoaib
authors.initials: MS
authors.lastname: Akhtar
authors.forename: Qaiser
authors.initials: Q
authors.lastname: Jabeen
authors.forename: Sajid
authors.initials: S
authors.lastname: Bashir
authors.forename: Muhammad Nasir Hayat
authors.initials: MN
authors.lastname: Malik
authors.forename: Sabeha
authors.initials: S
authors.lastname: Karim
authors.forename: Muhammad Naveed
authors.initials: MN
authors.lastname: Mushtaq
authors.forename: Shahid
authors.initials: S
authors.lastname: Rasool
authors.forename: Fozia
authors.initials: F
authors.lastname: Latif
authors.forename: Nazia
authors.initials: N
authors.lastname: Tabbasum
authors.forename: Abdul Qayyum
authors.initials: AQ
authors.lastname: Khan
authors.forename: Haseeb
authors.initials: H
authors.lastname: Ahsan
authors.forename: Wasim
authors.initials: W
authors.lastname: Khan
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Javed
mesh_terms: D000818:Animals; D028142:Berberis; D001794:Blood Pressure / Q000187:drug effects; D003864:Depression, Chemical; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D011817:Rabbits
chemical_list: D010936:Plant Extracts; D004837:Epinephrine