Sex Differences in Aged Hypertensive 129sv Mice

Salt‐sensitive hypertension has become an enormous public health problem due to the recent increase of dietary salt intake in many countries. It is already known that female sex hormones have a protective effect regarding the increase of blood pressure. However, little is known about sex differences in the aged kidney. The goal of this study was to determine whether or not there are differences in blood pressure, ENaC alpha protein expression, and filamin protein expression in the aged kidneys of salt‐sensitive male mice when compared to female mice after salt loading. Male and female 129Sv mice were aged for 12 months and maintained on a normal salt diet (0.4% NaCl) before being salt loaded (8% NaCl) for 4 weeks. During this time, blood pressure was measured by tail cuff and electrolytes in the urine were measured using an electrolyte analyzer. Protein expression of ENaC alpha and filamin were measured by Western blotting and immunohistochemistry. The difference in blood pressure before and after salt loading was greater in the aged male 129Sv mice compared to the females. Before and after salt loading, the male mice showed higher urinary sodium levels than the female mice. There were no differences observed in urinary potassium levels between the male and female mice. Although ENaC alpha protein expression did not change, filamin A protein expression was augmented in the hypertensive aged male mice compared to the females. This data suggests that there are sex differences in the aged kidneys of hypertensive 129Sv mice that do not involve changes in ENaC alpha protein expression but may involve changes in actin cytoskeleton associated proteins.Support or Funding InformationThis project was funded by the U.S. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases (Grant K01 DK099617; to A.A.A.) and the University of Florida College of Medicine.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.