SODIUMThe MOST ABUNDANT cation in the ECFNormal range is 135-145
mEq/LMajor contributor of plasma osmolarity
FUNCTIONS1. participates in the Na-K pump2. assists in
maintaining blood volume3. assists in nerve transmission and muscle
contractionAldosterone increases sodium retention ANF increases
sodium excretion
POTASSIUMMOST ABUNDANT cation in the ICFNormal range is 3.5-5.0
mEq/LMajor electrolyte maintaining ICVF balance
FUNCTIONS1. maintains ICF Osmolality2. nerve conduction and
muscle contraction3. metabolism of carbohydrates, fats and
proteinsAldosterone promotes renal excretion of K+Acidosis promotes
exchange of K+ for H+
in the cell
CALCIUMMajority of calcium is in the bones and teethNormal serum
range 8.5-10 mg/dL
FUNCTIONS1. formation and mineralization of bones/teeth2.
muscular contraction and relaxation3. cardiac function4. blood
clotting5. enzyme activation
CALCIUMRegulation:GIT absorbs Ca+2 in the intestine with the
help of Vit. DKidney Ca+2 is filtered in the glomerulus and
reabsorbed
in the tubulesPTH increases Ca+2 by bone resorption, Ca+2
retention and activation of Vitamin DCalcitonin released when Ca+2
is high, it decreases Ca+ by excretion in the kidney
MAGNESIUMSecond to K+ in the ICFNormal range is 1.3-2.1
mEq/L
FUNCTIONS1. intracellular production and utilization of ATP2.
protein and DNA synthesis3. neuromuscular irritability
THE ANIONSCHLORIDEPHOSPHATESBICARBONATES
CHLORIDEThe MAJOR Anion in the ECFNormal range is 95-108
mEq/L
FUNCTIONS1. major component of gastric juice aside from H+2.
together with Na+, regulates plasma osmolality3. participates in
the chloride shift4. acts as chemical buffer
PHOSPHATESThe MAJOR Anion in the ICFNormal range is 2.5-4.5
mg/L
FUNCTIONS1. component of bones2. needed to generate ATP3.
components of DNA and RNAPTH decreases PO4 in blood by renal
excretionCalcitonin increases renal excretion of PO4
BICARBONATESPresent both in ICF and ECFNormal range- 22-26
mEq/L
FUNCTION1. regulates acid-base balance2. component of the
bicarbonate-carbonic acid
