Cardiotonic and vasoconstriction effects of aqueous methanolic extract of Paspalidium flavidum L.
The cardiovascular activity of aqueous methanolic extract of Paspalidium flavidum L. was evaluated on isolated rabbit heart and aorta. Heart rates, force of contraction and perfusion pressure were assessed in the presence of different concentrations of extract and adrenaline by using Langendorff's technique. Moreover, the vasoconstriction effects were studied in rabbit aorta using isolated organ bath. The results indicated that the extract (1ng-100 μ g/ml) exhibited a significant increase in heart rate, contractility and perfusion pressure of isolated rabbit's heart; with a maximum effect at 1ng/ml, which was comparable to adrenaline (1 μ g/ml). Similarly, adrenaline at doses from 1-10 μ g/ml produced a significant dose dependant increase in all the cardiac parameters. The cardiotonic effects of the extract were significantly blocked by propranolol (10(-5)M) while an increase in perfusion pressure was completely antagonized by verapamil (10(-6)M). Activity of cardiac marker enzymes was also significantly raised in the perfusate of isolated heart pretreated with the extract. In rabbit aorta, the extract exhibited a dose dependent vasoconstriction effect however it did not increase the tone of aorta when pre-treated with verapamil (10(-6)M). It is conceivable therefore; that the cardiotonic and vasoconstriction effects of the extract might be due to its agonistic actions on β-receptors and Ca(+2) channels.
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Alamgeer
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Muhammad Nasir
MN
Hayat-Malik
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Sajid
S
Bashir
College of Pharmacy, GC University Faisalabad, Pakistan.
Ikram Ullah
IU
Khan
University College of Pharmacy, Punjab University, Lahore, Pakistan.
Sabeha
S
Karim
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Muhammad Naveed
MN
Mushtaq
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Hafeez Ullah
HU
Khan
School of Pharmacy, The University of Faisalabad, Pakistan.
Muhammad
M
Rashid
Faculty of Pharmacy, University of Sargodha, Sargodha, Pakistan.
Huma
H
Naz
Department of Zoology, University of the Punjab, Lahore, Pakistan.
Sadia
S
Samreen
D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology*; D006109:Poaceae; D011817:Rabbits; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D002316:Cardiotonic Agents; D010936:Plant Extracts; D014662:Vasoconstrictor Agents