Clinical trial NCT00345124: The Effect of High and Low Sodium Intake on Urinary Aquaporin-2 in Essential Hypertension
Official title: The Effect of High and Low Sodium Intake on Urinary Aquaporin-2 in Essential Hypertension, During Basal Conditions and After Hypertonic Saline Infusion.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Essential Hypertension and Healthy Controls
Keywords: urinary aquaporin-2
ENaC
fractional sodium excretion
High/low sodium diet
Lead sponsor: Regional Hospital Holstebro
Sponsor class: OTHER
First posted: 2006-06-27
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER

Brief summary: The aim of the study is to test the following hypotheses:

* that the function and/or regulation of AQP2 and/or ENaC in the principal cells is abnormal in essential hypertension.
* if an abnormal function of the principal cells is present in essential hypertension, this will become more pronounced at high and low sodium intake.


Eligibility criteria: Inclusion Criteria:

* Caucasian men and women
* Age 18-65 years
* Arterial hypertension
* Body mass index between 18.5 and 30 kg/m2

Exclusion Criteria:

* Secondary hypertension
* Isolated systolic hypertension
* History or clinical signs of AMI, atrial fibrillation, disease of the heart valves, or chronic heart failure.
* Malignant disease
* Prior apoplexy
* alcohol or drug abuse
* Drug use except antihypertensives and oral contraceptives
* Abnormal biochemical screening of the blood regarding: red and white blood count, s-creatinine (\> 200 micromol/L), b-hemoglobin, p-Sodium, p- potassium, 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.
* abnormal electrocardiogram
* Blood donation within one month of the first examination day
* Unwillingness to participate

Primary outcomes:
measure: u-AQP-2
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: fractional sodium excretion
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: p-vasopressin
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: p-aldosterone
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
Secondary outcomes:
measure: u-p-AQP-2
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: u-ENaC(alfa,beta,gamma)
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: CH2O
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: u-cAMP
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: uPGE2
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
measure: GFR
timeFrame: Before and after hypertonic saline infusion after 4 days on high and low sodium diet, respectively.
Other outcomes:
Locations:
city: Holstebro
country: Denmark
facility: Department of Medical Research, Holstebro Hospital
Study officials:
affiliation: Department of Medical Research, Holstebro Hospital, Denmark
name: Erling B. Pedersen, Professor
role: STUDY_CHAIR
affiliation: Department of Medical Research, Holstebro Hospital, Denmark
name: Carolina C. Graffe, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Graffe CC, Bech JN, Lauridsen TG, Vase H, Pedersen EB. Abnormal increase in urinary aquaporin-2 excretion in response to hypertonic saline in essential hypertension. BMC Nephrol. 2012 Mar 27;13:15. doi: 10.1186/1471-2369-13-15.