The Effect of High and Low Sodium Intake on Urinary Aquaporin-2 in Healthy Humans.

Study Overview
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Brief Summary
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The aim of the study is to test the hypothesis that the function and/or regulation of aquaporin 2 and/or endothelial sodium channels in the principal cells of healthy humans is abnormal at high and low sodium intake

Official Title
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The Effect of High and Low Sodium Intake on Aquaporin-2 in Healthy Humans, During Basal Conditions and After Hypertonic Saline Infusion.

Conditions
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Healthy Humans

Intervention / Treatment
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* Behavioral: High Sodium Diet
* Behavioral: Low Sodium Diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Caucasic men and women Age 18-65 years Body mass index less or equal to 30 Kg/m2 Exclusion Criteria: Arterial hypertension History or clinical signs of heart, brain, lung, kidney, malignant or endocrine organ disease. Abnormal biochemical screening of the blood regarding: red and white cell count, B-hemoglobin, P-sodium, P-potassium, P-creatinine, P-albumine, P- bilirubin, P-alanine aminotransferase, P- alkaline phosphatase, p-cholesterol and B-glucose. Abnormal screening of the urine regarding: blood, albumine and glucose. Alcohol or drug abuse Drug use except oral contraceptives Smoking Abnormal electrocardiogram Blood donation within one month of the first examination day Pregnancy Unwillingness to participate

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Intervention/Treatment |
| --- |
|Behavioral: High Sodium Diet|250-350 mmol|
|Behavioral: Low Sodium Diet|25-35 mmol|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| u-AQP-2 |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| fractional sodium excretion |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| p-aldosterone |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| u-pAQP-2 |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| u-ENaC(alfa-beta-gamma) |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| CH20 |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| ucAMP |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| uPGE2 |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 
| GFR |  | Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Urinary Aquaporin 2, High/low Sodium Diet, Fractional Sodium Excretion