Project titel: Oral potassium supplementation in healthy men - interactions with the renin-angiotensin-aldosterone system and the sympathetic nervous system Protocol number: KARAASS-1 EudraCT number: 2013-004460-66 Introduction The global burden of hypertension is huge. This project focuses on the role of potassium in human blood pressure regulation. A potassium rich diet lowers blood pressure and some studies have shown an increase in blood pressure during potassium depletion. Thus an inverse correlation between potassium intake and blood pressure exists. In this trial the objective is to test how an oral potassium supplementation, administered in form of the drug Kaleorid®, interacts with the renin-angiotensin-aldosterone system and the sympathetic nervous system. Methods This is a randomized clinical placebo-controlled double-blinded crossover trial. A group of healthy men will be randomized to either 4 weeks treatment with the drug Kaleorid®, 750mg, 3 tablets 3 times daily or to 4 weeks treatment with placebo. On day 26 in the first treatment period the participants meet at the hospital to start a 24-hours ambulatory blood pressure and collect a 48-hours urine sample. The same day a blood sample, an electrocardiogram (ECG) and a fat biopsy from the gluteal region will be done. The fat biopsy is expected to contain resistance vessels, which are to be investigated further in the laboratory. On day 28 in the first treatment period the participants meet at the hospital again and are tested with an intravenous Angiotensin II infusion followed by continuous measurement of blood pressure and the following aldosterone response (using blood samples). Blood pressure will be measured with Finger Plethysmography and vascular tonus will be evaluated with the use of Impedance Cardiography, Finger Plethysmography and Doppler Ultrasound measurements of blood flow before, during and after the Angiotensin II infusion. After this first period of treatment and testing a "washout" period of two weeks is inserted. After "washout", the participants crossover and starts the second treatment period. Feasibility All necessary authorities have approved the trial and all cooperation is established.
Name: Kaleorid, 750mg (trade name), Potassium chloride (active substance)Description: 4 weeks treatment with Kaleorid, 750mg, 3 tablets 3 times daily.Type: Drug
Name: PlaceboDescription: 4 weeks treatment with Placebo tablets, 3 tablets 3 times daily.Type: Drug
There is one SNP
Working with an in vitro model of aldosterone secretion in the form of the human adrenocortical cell line H295R, which has been proven to be a model for studying the function of the human adrenal cortex (13;14), we found interactions between extracellular potassium and components of the renin-angiotensin-aldosterone system (RAAS). --- H295R ---
The H295R cell line is a model of the human adrenocortical zona glomerulosa cells, which normally are the site of synthesis and secretion of aldosterone in the human body. --- H295R ---
It was found that stimulation of the H295R cells with high levels of extracellular potassium decreased the amount of Ang II type 1 receptors in the membrane of the cells, measured as a fall in the specific binding of radioactive labelled Ang II to the cells (15). --- H295R ---