LAUSR

Objectives: To observe the effects of dietary sodium intake on plasma inflammatory factors tumor necrosis factor alpha (TNF-&agr;), high-sensitivity C-reactive protein (CRP) and monocyte chemoattractant protein -1 (MCP-1) in normotensive adults. Methods: Thirty normotensive volunteers, aged 18 to 60, were selected to undergo a baseline survey, a low-sodium diet (51.3 mmol per day) for 7 days, a high-sodium diet (307.8 mmol per day) for an additional 7days. Thirty subjects were classified as salt sensitive group (SS, 10 subjects) or non-salt sensitive group (NSS, 20 subjects) on the basis of their mean arterial blood pressure (MAP) increase more than 10 percent at the end of the high-sodium phase compared with the low-sodium phase. Fasting blood samples were taken on the first day of baseline and on the sixth day of the two intervention phases. Plasma TNF-&agr; and MCP-1 concentration was measured using an enzyme-linked immunosorbent assay system, plasma hsCRP concentration was measured by immune nephelometry. Results: The prevalence of SS is 33%. After salt loading, no significant change was found in the plasma hsCRP concentrations; Whereas plasma TNF-&agr; level increased significantly in both of the two groups [(168.4 ± 67.8 vs. 42.1 ± 26.7)pg/ml, P < 0.01 and (129.8 ± 24.1 vs. 37.7 ± 15.8)pg/ml, P < 0.01, respectively]; Plasma MCP-1 was significantly higher during the high-sodium than the low-sodium phase in both of the two groups[(205.2 ± 64.2 vs. 166.3 ± 48.5)pg/ml, P < 0.01and (212.3 ± 52.2 vs. 143.6 ± 55.9)pg/ml, P < 0.01]. Conclusion: High-sodium diet can induce an inflammatory state, which may be independent of the salt sensitivity.