Acid-base balance via extracellular buffering

Acid-base balance via extracellular buffering" describes the physiological process by which the body maintains a stable blood and extracellular fluid pH, primarily through chemical buffering systems. The bicarbonate buffer system (carbonic acid/bicarbonate ion) is the chief extracellular buffer, responsible for about 80% of extracellular buffering[2][7]. Other contributors include the phosphate buffer system and plasma proteins[5][8]. These mechanisms act in concert to resist acute changes in hydrogen ion concentration, aiding the body in maintaining pH between 7.35 and 7.45, which is essential for cellular and systemic function[1][2][7]. Disruption of this buffering capacity can result in significant clinical disorders such as metabolic or respiratory acidosis/alkalosis. Pharmacologic agents like sodium bicarbonate or sodium citrate may be used to augment extracellular buffering in pathologic states or in high-intensity exercise to enhance acid clearance[3]. However, these are interventions targeting the process, not a discrete target molecule. This entry should NOT be treated as a canonical target (such as a protein, receptor, or enzyme), but rather as a description of a vital *physiological process* governed by molecular systems (chiefly bicarbonate, phosphate, proteins)[1][2][5][7][8].

Other names

Acid-base homeostasis (extracellular)extracellular pH bufferingsystemic acid-base balance

Chemical neutralization of H⁺ or OH⁻ ions via the bicarbonate or citrate buffer systems[3]