Effects of potassium on blood pressure regulation

Short-term changes (1 week) of potassium intake had no effect on elevated or normal blood pressure of 18 subjects. Potassium supplementation (100 mmol KCl/day) for 8 weeks caused a fall in blood pressure in 16 patients with mild hypertension. After cessation of potassium supplementation, blood pressure returned to "prepotassium" levels. In healthy volunteers, high potassium intake for 1 week resulted in a marked increase in intraleukocytic concentration of potassium. No change was observed in mean arterial pressure, cardiac index, or total peripheral resistance. The hemodynamic response to an intravenous infusion of ouabain was reduced during high potassium intake. Baroreceptor sensitivity rose during high potassium intake as demonstrated by the infusion of norepinephrine.