.Physiomodel.Electrolytes

Information

Electrolytes have four main functions:

• Establish the osmotic concentration gradients on cell membranes
• With balanced concentrations together with acid-base buffers establish the optimal acidity.
• With balanced concentrations together with radicals and antioxidants establish the optimal reduction potential.
• Electric signaling of cells such as neural action potential is possible because of passive/active selective membrane transports of electrolytes.

The main electrolytes are:

• Sodium (Na+). Reabsorption of sodium in kidney nephrons is one of the main power for reabsorption of water [Wright1982,Bruun1990]. This process is driven by aldosterone[Young1976,Stanton1986] and angiotensin II [Ofangii1986,Lohmeier1998,Seeliger1999]. Sodium is reabsorbed in each part of nephron in different way such as from proximal tubule [Wiederholt1967,Gullans1985], from loop of Henle [Cortney1966] or from distal tubule[Morgan1969]. Other type of excretion is by sweating[Epstein1999,Quinton1991,Sato1989].
• Potassuim (K+). The main compartment for potassium is intracellular fluid. Excretion of potassium by nephrons is driven also by aldosterone feedback control [Young1976, Young1983, Young1988]. The amount of secreted potassium to urine is dependent also on potasium plasma concentration [Toussaint1962] and on sodium excretion [Good1984,Young1984]. Other type of excretion is by sweating[Epstein1999,Quinton1991,Sato1989].
• Chloride(Cl-) is the main plasma anion. His renal excretion such as renal excretion of amonium and bicarbonates is driven by the acidity of plasma [Cogan1979,Sartorius1949]. Other type of excretion is by sweating[Epstein1999,Quinton1991,Sato1989].
• Amonium(NH4+) is formed and excreted in kidney to compensate plasma hydrogen ions concentration[Rodriguez-Nichols1984], because its production consume the free hydrogen ions changing to a strong cation at pH<=7.4.
• Phosphates(H2PO4-, HPO4^2-) and sulphate(SO4^2-) has no renal reabsorption, which means, that their excretion to urine is dependent only on Donnan's equilibrium on glomerular membrane [Donnan1911].

Contents

Name	Description
AcidBase	Body Acid-Base Balance
Sodium	Body Sodium Distribution
Potassium	Body Potassium Distribution
Chloride	Body Chloride Distribution
Phosphate	Body Phosphate Distribution
Sulphate	Body Sulphate Distribution
NH4	Body Amonium Distribution
Calcium
Calcium2
SweatGlandSalt
Bladder
ElectrolytesProperties
Electrolytes
IO_Bus

Revisions

Copyright © 2008-2015 Marek Matejak, Charles University in Prague.