CALCIUM Flashcards
[?]most common element
5th
[?] of Ca in the human adult is ectracellular
~25 mol (1 kg)
bones and teeth - most abundant
(99%)
as [?] - essential component of normal bone; makes up the bone mineral and matrix of the teeth
hydroxyapatite
soft tissues and the ECF
(~1%)
CALCIUM
Skeleton
Soft tissues
ECF
Total
99%
1%
<0.2%
1000g (25 mol)
PHOSPHATE
Skeleton
Soft tissues
ECF
Total
85%
15%
<0.1%
600g (19.4 mol)
MAGNESIUM
Skeleton
Soft tissues
ECF
Total
55%
45%
1%
5g (1.0 mol)
is protein bound
45%
is bound to albumin
80%
are bound to globulins
20%
is complexed with high molecular weight molecules such as citrate and phosphate; lactate and bicarboante
10%
are ionized/free or in their free form
45%
Primary hypoparathyroidism
Hypocalcemia
Hypomagnesemia
Hypocalcemia
Hypermagnesemia
Hypocalcemia
Acute pancreatitis
Hypocalcemia
Vit. D deficiency
Hypocalcemia
Primary hyperparathyroidism –
Hypercalcemia
adenoma or glandular hyperplasia
Hypercalcemia
Hyperthyroidism
Hypercalcemia
Malignancy
Hypercalcemia
Multiple myeloma
Hypercalcemia
Increased Vit. D
Hypercalcemia
Acidification of the sample (to dissociate Ca from proteins)
Dye-binding Methods
Dye-binding Methods dyes
Ortho-cresolphthalein complexone (CPC)
Arsenazo III dye
Uses 8-hydroxyquinoline to prevent mg interference
Ortho-cresolphthalein complexone (CPC)
reference method for total Calcium
- AAS
rarely used in the clinical setting
- AAS
membrane that selectively, but reversibly bind Ca
- ISE
Total Calcium - Serum, Plasma
2.15 - 2.5 mmol/L
Ionized Calcium - Serum
1.16 - 1.32 mmol/L
Ionized Calcium - Plasma
1.03 - 1.23 mmol/L
Total Calcium 24 Hour Urine
2.5 - 7.5 mmol/day (100 - 300 mg/day)
Total Ca
Serum or Li-H plasma (collected w/o stasis)
Ionized Ca - samples collected anaerobically
heparinized blood
timed collection; acidified w/ 6 mol/L HCl to prevent precipitation
Urine
Regulation of cell functions
(inorganic messenger)
Determines activity of several enzymes by combining w/ [?]
calmodulin
- small protein found in all nucleated cells
Calmodulin
calcium-modulated protein
calmodulin
type of Ca-binding protein found on the cell cytoplasm
calmodulin
= acts as regulator
Ca + Calmodulin
Regulates muscle contraction: binds to
troponin
: Ca-binding protein subunit
Trop C
not found in the heart but in the thin filaments or muscle
Trop C
important for active muscle contraction
Trop C
Ca stabilizes and hold contents
Regulates cell membrane permeability
Controls secretions of some endocrine glands (?)
PT gland, Thyroid C cells
PT gland:
Thyroid C cells:
PT hormone
Calcitonin
Blood coagulation
– first activated during tissue damage
Factor 3 (Thrombokinase)
– reacts w/ Factor 3 to form Thrombin
Factor 2
– converts fibrinogen to fibrin
Thrombin
– makes up the mesh that makes up clot
Fibrin
Rigidity to [?]
bones & teeth
Lack of Ca: prone to
skeletal muscle disorders
