PMC

Shown are the known mechanisms that regulate external potassium balance and the pathways for net potassium movement associated with meal-driven potassium intake (Panel A) and with between-meal fasting (Panel B). Meal-driven potassium intake initiates both an increase in potassium excretion and sequestration of potassium in liver and skeletal muscle. Increased excretion is driven by reactive mechanisms, which can be either dependent on the plasma potassium level (negative-feedback regulation) or independent of the plasma potassium level (feed-forward regulation) initiated at splanchnic receptors. The circadian rhythm drives a predictive regulation of the tubule mechanisms responsible for potassium excretion, generated by a central clock and transmitted to circadian clocks in the tubule cells responsible for variations in potassium excretion. This rhythm enhances excretion during the active daylight phase and diminishes it during the inactive nighttime phase. In combination, these components provide maintenance of total body potassium levels within narrow limits without appreciable changes in the plasma potassium level. Between periods of meal intake, potassium is released from intracellular stores (primarily liver and skeletal muscle) for excretion.

1a: Potassium level in the spot urine sample vs. potassium level in the 24-hour urine collection (r = 0.47, P<0.001). 1b: Potassium level in the spot urine sample vs. 24-hour urinary potassium excretion (r = 0.28, P<0.001). 1c: Potassium/creatinine ratio in the spot urine sample vs. 24-hour urinary potassium excretion (r = 0.38, P<0.001). 1d: Potassium/creatinine ratio in the spot urine sample vs. 24-hour urinary potassium/creatinine ratio (r = 0.69, P<0.001).

Correction of metabolic acidosis from potassium citrate versus potassium chloride administration and associated effects on serum potassium concentration. (A) Changes in serum bicarbonate concentration (S-HCO₃⁻) over 12 months in relation to potassium citrate or potassium chloride intake. (B) Changes in serum potassium concentration over 12 months in relation to potassium citrate or potassium chloride intake. *P≤0.05 versus potassium chloride; ^†P≤0.05 versus baseline for potassium chloride; ^‡P≤0.01 versus baseline for potassium citrate. S, serum; M, month.

A principal component analysis for chlorophylls content, fresh and dry weight, total phenolics content, and antioxidant activity of basil leaf extracts influenced by drought stress and potassium bicarbonate application. CWW1–“Cinnamon” well-watered; CWW2–“Cinnamon” well-watered and sprayed with potassium bicarbonate; CDS1–“Cinnamon” drought stress; CDS2–“Cinnamon” drought stress and sprayed with potassium bicarbonate; RWW1–“Red Rubin” well-watered; RWW2–“Red Rubin” well-watered and sprayed with potassium bicarbonate; RDS1–“Red Rubin” well-watered; RDS2–“Red Rubin” well-watered and sprayed with potassium bicarbonate; DWW1–“Dark Opal” well-watered; DWW2–“Dark Opal” well-watered and sprayed with potassium bicarbonate; DDS1–“Dark Opal” drought stress; DDS2–“Dark Opal” drought stress and sprayed with potassium bicarbonate; PWW1–“Palla Compato” well-watered; PWW2–“Palla Compato” well-watered and sprayed with potassium bicarbonate; PDS1–“Palla Compato” drought stress; PDS2–“Palla Compato” drought stress and sprayed with potassium bicarbonate; AWW1–“Aromatico Della Riviera Ligure” well-watered; AWW2–“Aromatico Della Riviera Ligure” well-watered and sprayed with potassium bicarbonate; ADS1–“Aromatico Della Riviera Ligure” well-watered; ADS2–“Aromatico Della Riviera Ligure” well-watered and sprayed with potassium bicarbonate.