Effects of D-Polymannuronic sulfate on potential-dependent and/or receptor-operated calcium channel in rat aortic rings / 中国海洋药物

The effects of D-polymannuronic sulfate (DPS) on the norepinephrine (NA) or potassium chloride (KCL)-induced contraction of rat aortic rings were studied in this paper. The results showed that DPS at the final concentration of Img ? L-1 inhibited the contraction of aortic rings e-voked by NA or KCL and shift doseresponse curves for NA or KCL to the right in a non-parallel fa-sion and depressed their maximal response, implicating that DPS afforded the noncompetitive antagonism on contraction of rat aortic rings induced by NA or KCL. This finding suggested that DPS exerted an inhibitory action of potential-dependent calcium channel and that of receptor-operated calcium channel in vascular smooth muscle.