Study on naringenin for renal artery diastole in rats and its mechanisms

Hou Xiaomin; Qin Xiaoj iang

doi:10.3969/j.issn.10096493.2014.25.010

Abstract：Obj ective:To probe into the vasodilation effect of naringenin for rat renal artery rings and its mechanism.Methods:DMT capillary tension recorder and Powerlab tension transducer were used to record its changes of tension.The renal artery rings received pre contraction treatment with potassium chloride (60 mmol/L)or phenylephrine (10-5 mol/L)reached to the platform,and the concentration dependent vaso-dilation was implemented in the renal arteries by using naringenin (10-6 mol/L~10-4 mol/L),then to measure the vasodilation percentage of pre contracted renal artery.Before and after naringenin pre incubation (selected concentration was RC50 values calculated in diastole experi-ments )contraction amplitude changes of the renal arteries were ob-served after treatment with 60 mmol/L KCl or 10-5 mol/L phenyleph-rine.After potassium chloride or phenylephrine were used for pre con-striction of renal artery up to the platform,and incubation reached the platform with Kir channel inhibitor barium chloride (BaCl2 10-4 mol/L) and KCa channel inhibitor tetraethylammonium (TEA,10-3 mol/L)for 1 5 min,then in turn the different concentrations of naringenin (1 0-6 mol/L~1 0-4 mol/L)was added for relaxing the renal artery and then to observe the influence of BaCl2 and TEA on vasodilation of renal artery by naringenin.Results:Naringenin within 1 0-6 mol/L~1 0-4 mol/L had a concentration dependent vasodilation for KCl or phenylephrine pre constricted isolated rat renal artery rings;naringenin incubation in ad-vance can reduce contraction amplitude of rat kidney artery rings by KCl or phenylephrine to some extent,and it decreased by (53.10±2.43)%and (46.39±3.24)% respectively;Kir channel inhibitor barium chloride (1 0-4 mol/L)didn’t have significant influence on vasodilation effect of naringenin for 60 mmol/L KCl or 10-5 mol/L phenylephrine pre con-stricted renal artery rings,and KCa channel inhibitor tetraethylammoni-um (TEA,10-3 mol/L)had a certain degree of inhibition for maximum amplitude of vasodilation of naringenin for 60 mmol/L KCl or 10-5 mol/L phenylephrine pre constricted renal artery.Conclusion:Naringenin has the concentration dependent vasodilation effect for isolated renal arteri-al vascular rings in rats receiving potassium or phenylephrine pre con-stricted treatment;the vasodilation effect of naringenin on the renal ar-tery rings is related with calcium activated potassium channels KCa .