Background Increased potassium intake has been shown to lower blood pressure (BP) even in the presence of high sodium consumption however the role of dietary potassium on vascular function has received less attention. The aim of this study was to evaluate the relationship between habitual intake of sodium (Na) and potassium (K) and measures of arterial stiffness and wave reflection. Methods Thirty-six young healthy adults (21 M, 15 F; 24 ± 0.6 yrs; systolic BP 117 ± 2; diastolic BP 63 ± 1 mmHg) recorded their dietary intake for 3 days and collected their urine for 24 hours on the 3rd day. Carotid-femoral pulse wave velocity (PWV) and the synthesis of a central aortic pressure waveform (by radial artery applanation tonometry and generalized transfer function) were performed. Aortic augmentation index (AI), an index of wave reflection, was calculated from the aortic pressure waveform. Results Subjects consumed an average of 2244 kcals, 3763 mg Na, and 2876 mg of K. Average urinary K excretion was 67 ± 5.3 mmol/24 hr, Na excretion was 157 ± 11 mmol/24 hr and the average Na/K excretion ratio was 2.7 ± 0.2. An inverse relationship between AI and K excretion was found (r = -0.323; p < 0.05). A positive relationship between AI and the Na/K excretion ratio was seen (r = 0.318; p < 0.05) while no relationship was noted with Na excretion alone (r = 0.071; p > 0.05). Reflection magnitude, the ratio of reflected and forward waves, was significantly associated with the Na/K excretion ratio (r = 0.365; p <0.05) but not Na or K alone. PWV did not correlate with Na or the Na/K excretion ratio (p > 0.05) but showed an inverse relationship with K excretion (r = -0.308; p < 0.05). Conclusions These data suggest that lower potassium intakes are associated with greater wave reflection and stiffer arteries in young healthy adults.

Omega‐3 supplementation has been shown to be beneficial in reducing oxidative stress and inflammation. The purpose was to determine if 12 weeks of a high omega‐3 fatty acid diet would reduce age associated increases in myocardial oxidative stress and inflammation. 20 mature (M) (6 mo.) and 20 older (O) (15 mo.) SD rats were assigned to 2 diet groups: Control (CON) or Fish Oil (FO). Following the diet, animals were sacrificed and left ventricular heart tissue was harvested. Interleukin‐6 was significantly lower in MFO vs. OCON and OFO (26.58±0.67 vs. 37.77±3.85 & 37.68±2.23 pg/mg, respectively; p<0.05). Tumor necrosis factor‐alpha was not different among groups. Hydrogen peroxide production (H2O2) was reduced by FO treatment (p<0.01) but not significant in regards to age. However, OFO H2O2 trended towards significance vs. OCON (0.10±0.02 vs. 0.12±0.01 uM/mg ptn; p=0.09). A significant effect was seen for catalase with age (p<0.05), between MCON and OCON (3.04±0.38 vs. 4.49±0.36 U/mg ptn; p<0.05) and trended towards significance in OFO (3.04±0.38 vs. 4.25±0.36 U/mg ptn; p=0.1). There were no differences among groups for superoxide dismutase (p>0.05). These results suggest age‐associated increases in myocardial inflammation regardless of FO treatment. However, FO supplementation appears to increase some myocardial antioxidant activity and reduce H2O2.Supported by UD Research Foundation Grant

Arginase (Arg) impairs endothelial‐dependent relaxation (EDR) in aging and hypertension. The PURPOSE of this study was to determine if Arg inhibition or L‐arginine (L‐arg) treatment improves EDR in chronic kidney disease (CKD).