SEX, METABOLIC AND PHARMACOLOGICAL MODULATORS OF SODIUM HANDLING IN POPULATION WITH PREVAILING SODIUM INTAKE

Abstract

Objective: Renal sodium handling is associated with sex, ethnic, central adiposity and hypertensive treatment. Design and method: In a sample of caucasian population without diuretic treatment (351 subjects) with prevailing sodium consumption (153,6 mmol/d), we studied the associations between renal sodium reabsorption in proximal (FPRNa) and distal (FDRNa) tubules assessed by endogenous lithium clearance, daily sodium intake measured by 24-h excretion of sodium (UNaV) and measures of obesity in the context of chronic treatment with ACEI or ARB. Results: In the entire population in linear regression model, we found a relation between sex and FPRNa (β = 1.06 ± 0.30, P = 0.0005), with higher sodium reabsorption in proximal tubules in men. In subjects with FPRNa below the median value, we displayed a significant reverse relation between FPRNa and ACEI/ARB treatment (β = -0.40 ± 0.18, P = 0.03) with no relation for BMI (P = 0.42). Contrary, in subjects with FPRNa above the median value, a significant positive relation between FPRNa and BMI (β = 0.10 ± 0.03, P = 0.004) was revealed, with no relation for ACEI/ARB treatment (P = 0.55). For FDRNa (P > 0.10) and UNaV (P > 0.06) we found no relation for ACE/ARB treatment in entire population and after divided by median. Conclusions: We found that sex, obesity and chronic treatment with ACEI/ARB influence sodium reabsorption in renal proximal tubules. This may impact both on the research and clinical practice.