Effect of Polyphenolic Compounds on the Renal Na⁺,K⁺‐ATPase during the Restoration of Normotension after Experimentally Induced Hypertension in Rats

Abstract

It is commonly known that consumption of foods and beverages rich in polyphenols is associated with a lower incidence of cardiovascular disease. The purpose of this study was to assess whether the application of red wine polyphenols influences the kinetic properties of renal Na(+),K(+)-ATPase in rats in which hypertension has been experimentally induced by the nitric oxide synthase inhibitor L-NAME. Treatment with polyphenols during the recovery from hypertension to normotension resulted in the complete revival of the functional properties of the Na(+),K(+)-ATPase, as indicated by the total restoration of K(m), K(Na) (concentration of Na(+) necessary to achieve half-maximal reaction velocity) and V(max) for enzyme activation by ATP and/or Na(+) to pre-hypertension values. Two positive effects of polyphenols during the recovery period are indicated: a restoration of the affinity of the ATP and Na(+) binding sites to control values and a probable increase in the number of Na(+),K(+)-ATPase molecules to a level comparable to that in control conditions, as suggested by the complete renewal of V(max).