Cardiovascular and airway relaxant activities of peony root extract.
Paeonia emodi (peony) is a well known plant used medicinally to treat hypertension, palpitations, and asthma. Despite its popularity, there are few reports in the scientific literature examining its use in such conditions. We prepared a 70% ethanolic extract of peony root (Pe.Cr) and applied it to segments of guinea pig atria and trachea and rat aorta suspended separately in tissue baths. Activity against arachidonic acid (AA)-induced platelet aggregation was measured in human platelet-rich plasma. Airway relaxant effect was evaluated against acetylcholine (ACh)-induced airway contraction in mouse lung slices loaded with fluo-4. Pe.Cr (0.3-10 mg/mL) showed an atropine-resistant negative inotropic effect in atria. In rat aorta, an endothelium-independent vasodilatory effect (0.3-10 mg/mL) was seen in phenylephrine- and high-K+-induced contractions. Pe.Cr (0.01-1 mg/mL) also inhibited AA-induced platelet aggregation. In isolated trachea, Pe.Cr (0.3-10 mg/mL) relaxed carbachol- and histamine-induced contractions independently of beta-adrenergic receptors. In mouse lung slices, Pe.Cr (0.3-1 mg/mL) inhibited ACh-induced airway narrowing and oscillations of intracellular Ca2+ in airway smooth muscle cells. The results showed cardiosuppressant, vasodilatory, antiplatelet, and tracheal and airway relaxant activities of peony, providing potential justification for its medicinal use in different hyperactive cardiovascular and respiratory disorders.
Ghayur
Muhammad N
MN
Department of Medicine, McMaster University, St. Joseph's Hospital, 50 Charlton Avenue East, Hamilton, ON L8N4A6, Canada. nghayur@mcmaster.ca
Gilani
Anwarul H
AH
Rasheed
Huma
H
Khan
Abdullah
A
Iqbal
Zafar
Z
Ismail
Muhammad
M
Saeed
Sheikh A
SA
Janssen
Luke J
LJ
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001095:Arachidonic Acids / Q000494:pharmacology; D020013:Calcium Signaling / Q000187:drug effects; D000431:Ethanol; D005260:Female; D006168:Guinea Pigs; D006325:Heart Atria; D007091:Image Processing, Computer-Assisted; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects; D008297:Male; D018613:Microscopy, Confocal; D009119:Muscle Contraction / Q000502:physiology; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D029596:Paeonia / Q000737:chemistry*; D010936:Plant Extracts / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012997:Solvents; D014132:Trachea / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology
D001095:Arachidonic Acids; D010936:Plant Extracts; D012997:Solvents; D014665:Vasodilator Agents; D000431:Ethanol