Effect of astragaloside Ⅳ on contraction and relaxation in isolated rat aortic rings / 中国药理学通报

ABSTRACT

Aim To study the effect and investigate the underlying mechanism of astragaloside Ⅳ on contraction and relaxation in isolated rat aortic rings.Methods The relaxation effect of astragaloside Ⅳ(1～100 mg?L~(-1))on phenylephrine-preconstricted aorta ring was recorded.The effect of astragaloside Ⅳ on the contraction induced by cumulative phenylephrine,KCl or CaCl_2,was recorded respectively.Results Astragaloside Ⅳ dilated aortic vessels in a dose-dependent manner,which was partly inhibited by preincubation with non-selective nitric oxide synthase inhibitor,guanylyl cyclase inhibitor and cyclooxygenases inhibitor indomethacin.Astragaloside IV could also antagonize phenylephrine-,KCl-and CaCl_2-induced vessel contraction.Conclusion Astragaloside IV dilated aortic vessels partially though endothelium-dependent NO pathway and inhibited vessel contraction via interfering Ca~(2+) influx.