Extracellular fluid

Extracellular fluid usually denotes all body fluid outside of cells. The remainder is called intracellular fluid.

In some animals, including mammals, the can be divided into 2 major subcompartments, interstitial fluid and blood plasma. The extracellular fluid can be further divided into 2 minor subcompartments, transcellular fluid and lymph.

In humans, the normal glucose concentration of extracellular fluid that is regulated by homeostasis is approximately 5 mM.

The pH of extracellular fluid is tightly regulated by buffers around 7.4.

Contents of ECF
Main Cations: Sodium (140 mM) Potassium (4 mM) Calcium (2 mM)

Main Anions: Chloride (110 mM) Hydrogen Carbonate (26 mM)

It is poorer in proteins compared to intracellular fluid