Calcium and Parathyroids Flashcards
Why is calcium so important within the body?
- Nerve conduction
- Bone formation
- muscle formation
- Blood coagulation
- Cerebral and cardiac function
- Capillary permeability
- Cell growth and division
- Neurotransmitter action
T/F: The body contains 1-2 kilograms of calcium.
TRUE
Where at is the calcium found in the body and how much in each area?
- Skeleon 98%
- Plasma 0.03%
- ECF 0.1%
- Cells 1 %
T/F: 50% of calcium is Ionized (active form).
TRUE
What are the most important aspects of calcium on the body?
- Heart
- Nervous system,
- Bone formation
Where is the other 50% of the calcium that is non-ionize?
- 41% protein bound (Albumin)
- 9% Combined with anions (DIFFUSIBLE)
How much Ca++ from the bone is readily exchangeable?
0.5%
What will be seen with HYPOcalcemia?
-Nervous System EXCITEMENT \:increased neuronal permeability to Na (easy action potential) \:Tetany \:Seizures \:Chvosteks sign
What will be seen with HYPERcalcemia?
-(Major S/S) Skeletal muscle weaknes
-Nervous system depression
:(Short) QT, (Long) PR,
:constipation
:anorexia
:
What is the treatment for HYPERcalcemia?
- Maintain UOP
- hydrate
- Mithramycin
How much phosphorus is kept within the body?
-1 kilogram
Where at in the body is phosphorus found?
- Skeletal (85%)
- muscle/tissue (15%)
- ECF (1%)
T/F: Phosphorus is easily absorbed in the GI tract.
TRUE
Where are the parathyroids located?
- 4 glands
- Behind the thyroid in the upper and lower poles
What cells makeup the parathyroid?
- chief cells
- oxyphil cells
T/F: The oxyphil cells in the parathyroid release the parathyroid hormone.
FALSE (Chief cells release the parathyroid hormone)
Synthesis and secretion of the _________ hormone is related to calcium _________ in the _____.
parathyroid, concentrations, blood
What will enlarge the parathyroids?
- prolong stimulation
- pregnancy
- lactation
T/F: Decrease in calcium concentration in the extracellular fluid increases the secretion of the PTH.
TRUE
Where does the PTH, cholecalciferol, and Calcitonin work at in the kidneys?
-proximal tubules
What is bone resportion?
The process by which osteoclasts break down bone and release calcium from bone fluid to blood
What is PTH action within the body?
- Increase bone resorption
- Increases reabsorption of Ca++ in the distal tubules
- Decreases reabsorption of phosphate in the renal tubules
- Increases the production of 1,25-dihydroxycholecalciferol
What does 1,25-dihydoxycholecalciferol do?
-Vit. D metabolite which enhances intestinal Ca++ absorption
Increases in PTH in the body results in what?
- Serum: Increased calcium, decreased phosphate
- Urine : Decreased calcium, increased phosphate
