Urinary biomarkers (u-NKCC2, u-ENaC-gamma and u-AQP2) reflects the activity of the sodium- and water channels in the human kidney. Changes in the sodium-and water channel activity can be induced by blocking the sodium channels with diuretics in healthy subjects
1. Urinary biomarkers (u-NKCC2, u-ENaC-gamma and u-AQP2) reflects the kidneys transport of sodium and water in the nephron. 2. Changes in the sodium-and water channel activity is induced by blocking the NCC channels with thiazide and ENaC channels with amiloride and by intervention with hypertonic NaCl The changes in sodium-and water channels are followed by changes in extracellular and intracellular fluids, central bloodpressure and the plasma concentration of vasoactive hormones. The purpose of this study is to investigate the changes in urinary biomarkers (u-NKCC2, u-ENaC-gamma and u-AQP2), extra- and intracellular fluid compartments, central bloodpressure and the plasma concentration of Vasoactive hormones in healthy subjects under a) treatment with Amiloride and Thiazide at baseline and b) after and acute infusion with hypertonic saline. Subjects will be examined on three examination days. Four days prior to the examination days the subjects will consume a standard diet based on amount of sodium and calories and randomized to treatment with either thiazide, amiloride or placebo twice daily for 5 days. On the examination days the subjects receive an infusion with hypertonic saline. Renal function is measured by renal clearance of 51Cr-EDTA. Urinary biomarkers (u-NKCC2, u-ENaC-gamma and u-AQP2) will be measured to evaluate the activity of water- and sodium channels in the nephron, changes in fluid compartments are measured by body composition monitor. Central blood pressure is measured by sphygmocor.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
DIAGNOSTIC
Masking
TRIPLE
Enrollment
24
hypertonic saline 3.0% 7 ml/kg
Medical Research
Holstebro, Denmark
urinary biomarkers
Urinary excretion of epithelial sodium channels (ENaC), Sodium-potassium-2chloride transporters (NKCC2) and aquaporin2 channels (AQP2) before, during and after fluid infusion
Time frame: baseline, 0 hours and 1.5 hours after intervention
vaso active hormones
plasma concentrations of: renin, Angiotensin II, aldosterone, Vasopressin, ANP and BNP
Time frame: baseline, 0 hours and 1.5 hours after intervention
central blood pressure
measured by applanation-tonometry
Time frame: baseline, 0 hours and 1.5 hours after intervention
intracellular (ICV)- and extracellular volume (ECV)
change in ICV and EVC from baseline and after intervention measured in liters by body composition monitor (BCM)
Time frame: baseline, 0 hours and 1.5 hours after intervention
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.