Relaxation effect of total flavonoids from peanut hull on rat thoracic aorta

Objective: To explore the vasoactive effect of total flavonoids from peanut hull (TFPH) on rat thoracic aortas and its potential mechanism. Methods: The tension of thoracic aortic rings isolated from male Sprague-Dawley rat was measured in the organ bath system. Results: 1. TFPH (20-640 mg/l) concentration-dependently induced vasorelaxation (P <; 0.01 vs. control) in aortas previously contracted by KCl or phenylephrine (PE) regardless of endothelium. 2. The EC50 (80 mg/l) concentration of TFPH reduced Ca²⁺-induced contraction (P <; 0.01 vs. control) in endothelium-denuded aortas preincubated with KCl or PE. Conclusion: The vasodilatation induced by total flavonoids from peanut hull may involve the inhibition of vascular smooth muscular voltage- and receptor-dependent Ca²⁺ channels.