2S [LAB]: Magnesium Flashcards
4th most abundant cation in the body
Magnesium
2nd most abundant intracellular ion
Magnesium
How many percent of magnesium is present in the bone?
53%
How many percent of magnesium is present in the muscle, other organs, and soft tissues?
46%
How many percent of magnesium is present in the serum?
<1%
1/3 of magnesium in the serum is bound to ___
Proteins (albumin)
Which organ is responsible in the overall regulation of Mg2+?
Kidneys
Which hormone increases renal and intestinal Mg2+ reabsorption?
Parathyroid hormone
Hormones that increases renal excretion of Mag2+
Aldosterone
Thyroxine
The principle of total Mg2+ determination
Colorimetric
The most frequent colorimetric method used for Mg2+ determination
Methylthymol blue or Magon or Xylidyl blue
The Formazan dye in Mg2+ determination has an end color of ___
Red
The Calmagite method in Mg2+ determination has an end color of ___
Reddish violet
Reference method for Mg2+ determination
Atomic Absorption spectrophotometer
Anticoagulant preferred in Mg2+ determination
Lithium heparin
Anticoagulants discouraged in Mg2+ determination
EDTA
Oxalate
Citrate
Preferred urine specimen for magnesium determination
24 hr urine
Reference range of Mg2+ in serum
0.63-1.0 mmol/L
Ion that acts as a cofactor of cellular enzymes and is important in DNA replication and transcription
Magnesium
Important in ion transport and nerve conduction
Magnesium
How many percent of magnesium is reabsorbed in the DCT?
25-50%
How many percent of magnesium is reabsorbed in the ascending limb?
50-60%
How many percent of magnesium is reabsorbed in the PCT?
2-5%
Identify the effect on magnesium:
Hyperthyroidism/ Hyperparathyroidism
Hypomagnesemia
