Potassium in Skeletal Muscle in Untreated Primary Hypertension and in Chronic Renal Failure,Studied by X-ray Fluorescence Technique

ABSTRACT Muscle biopsy specimens form 22 patients with pirmary hypertension, 10 patients with chronic renal failure and 21 healthy normotensive controls were analyzed using a Kevex 0600 X-ray spectrometer. Muscle potassium (MK), calcium (MCa), sulphur (MS) and phosphorus (MP) were determined. In the patients wih primary hypertension, MK was decreased compared to the controls (p<0.001), MCa was increased (p<0.05), MS was decreased (p<0.05) and no difference was seen in MP. In the patients with chronic renal failure, MK was decreased compared to the controls (p<0.001), MCa showed no difference compared to the controls, whereas both MP and MS were lower (p<0.05 and p<0.001). It was concluded that intracellular potassium is low both in primary hypertension and chronic renal failure. In chronic renal failure the potassium decrease is probably secondary to loss of cellular potassium capacity, whereas in primary hypertension an inhibition of the sodium, potassium, adenosine triphosphatase is suggested as the cause of the low potassium.