Calcium plays a vital role in several biological processes including normal neuromuscular transmission, muscular contractility, cellular signaling, enzyme function, and blood coagulation. Hence, the appropriate control of calcium homeostasis is vital to the well-being of the organism. Severe calcium deficiency…
Although bone harbors almost all of the body stores of calcium, the kidneys serve as the regulator of calcium homeostasis. Calcium filtered at the glomerulus is extensively reabsorbed by proximal tubules. This recovery proceeds without hormonal regulation and is governed…
Cell surface sensors for extracellular Ca 2+ and Mg 2+ provide an important mechanism for the regulation of diverse physiological processes by extracellular divalent mineral ions. These ion sensors function as “calciostats” for Ca 2+ and/or Mg 2+ that not…
The SLC4 ( s o l ute c arrier 4) family is a group of a membrane proteins that share sequence homology and in general mediate the transport of bicarbonate. It should be noted that bicarbonate transport is not unique…
Magnesium plays a vital role in virtually all cellular processes as a cofactor of enzymes, a structural element of proteins and nucleic acids, and a modulator of receptors and ion channels. The control of magnesium homeostasis primarily resides in the…
Respiratory acid–base disorders are those abnormalities in acid-base equilibrium that are initiated by a change in blood carbon dioxide tension (PCO 2 ). An increase in PCO 2 (hypercapnia) acidifies body fluids and initiates the acid-base disturbance known as respiratory…
Abstract Metabolic acidosis is the acid–base disturbance that is initiated by a primary decrease in the plasma [HCO 3 − ]. The acidemia leads to a time-dependent and quantitatively predictable ventilatory response, i.e., a secondary decrease in CO 2 tension…
Homeostatic control of acid–base parameters within discreet limits is vital to all living organisms. Acid–base disturbances are conditions that reflect abnormal underlying physiologic processes that can stem from a broad range of etiologies. In humans with a filtration-reabsorption nephron design,…
The maintenance of systemic acid-base balance within relatively narrow limits is essential for life. However, the development of metabolic acidosis, which is characterized by a significant decrease in plasma pH and bicarbonate ions, is a common clinical condition. Metabolic acidosis…
The regulation of acid–base balance depends on renal mechanisms that determine net excretion of acid or base and breathing mechanisms that alter the partial pressure of carbon dioxide (PCO 2 ) in body tissues. The level of ventilation (breathing) is…