Changes

*reduced concentration of potassium in the ECF leads to plasma membranes hyperpolarization resulting in decreased firing of action potentials.  This causes skeletal muscle weakness and cardiac abnormalities.

*reduced concentration of potassium in the ECF leads to plasma membranes hyperpolarization resulting in decreased firing of action potentials.  This causes skeletal muscle weakness and cardiac abnormalities.

*increased concentration of potassium in the ECF leads to membrane depolarisation which is inappropriately triggered by action potentials.  This can make the membrane insensitive to further stimulation causing cardiac abnormalities.

*increased concentration of potassium in the ECF leads to membrane depolarisation which is inappropriately triggered by action potentials.  This can make the membrane insensitive to further stimulation causing cardiac abnormalities.

==Sources of Potassium==

==Sources of Potassium==

Potassium is absorbed via passive diffusion from the [[Small Intestine Overview - Anatomy & Physiology|small intestine]] and via active transport from the [[Colon - Anatomy & Physiology|colon]]. It is regulated efficiently by [[Aldosterone|aldosterone]] levels and recovery from cellular breakdown during haemolysis or tissue damage.

Potassium is absorbed via passive diffusion from the [[Small Intestine Overview - Anatomy & Physiology|small intestine]] and via active transport from the [[Colon - Anatomy & Physiology|colon]]. It is regulated efficiently by [[Aldosterone|aldosterone]] levels and recovery from cellular breakdown during haemolysis or tissue damage.

* However net reabsorption / secretion of potassium occurs in the distal tubule and first part of collecting duct

* However net reabsorption / secretion of potassium occurs in the distal tubule and first part of collecting duct

** Depends on bodies need

** Depends on bodies need

* Under the influence of [[Aldosterone]]

* Under the influence of [[Aldosterone|aldosterone]]

* This is where the amount of potassium excreted is determined

* This is where the amount of potassium excreted is determined

* Reabsorption occurs in the final part of the collecting duct

* Reabsorption occurs in the final part of the collecting duct

* The resulting increased cellular uptake of potassium results in it moving down the electrochemical gradient into the nephron

* The resulting increased cellular uptake of potassium results in it moving down the electrochemical gradient into the nephron

2.Potassium: High potassium = increased potassium excretion which triggers the release of aldosterone.

2.Potassium: High potassium = increased potassium excretion which triggers the release of aldosterone.

[[Category:Electrolytes]]

[[Category:Electrolytes]]