Term
| calcium homostasis regulation functions |
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Definition
Functions: component of a current flow across excitable membranes, fusion and release of vesicles and muscle contraction,
Promote coagulation
Formation and modeling of skeleton |
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Term
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Definition
| bone resorption cells which take calcium from bone and put it into the blood |
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Definition
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Term
| Parathyroid Hormone (PTH) |
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Definition
| Action: increases plasma Ca++, decreases plasma PO4, increases bone resorption |
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Term
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Definition
When plasma Ca++ levels are high:
decreases plasma Ca++, decreases plasma PO4, decreases bone resorption,
works against PTH |
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Term
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Definition
salmon calcitonin
Uses: Paget’s, acute hypercalcemia, osteoporosis, osteolytic bone metastases
MOA: inhibits calcium resorption/efflux |
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Term
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Definition
| Permit efficient absorption of dietary Ca, and phosphate( opposite of calcitonin), it increases plasma levels of PO4 and Ca++ |
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Term
| Vitamin D formulations and uses: |
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Definition
| Cholecalciferol — vitamin D3 Ergocalciferol— vitamin D2 25-OH-D3 1,25-OH-D3 (paricalcitol)(active) 1-OH-D3 Uses: hypocalcemia (low levels) hypoparathyroidism (low PTH) rickets -osteomalacia- Osteomalacia is the general term for the softening of the bones due to defective bone mineralization kidney disease (2° hyperparathyroidism |
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Term
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Definition
Calcium Salts (gluconate, lactate)
Uses: hypocalcimia (IV)
immediate treatment (iv) of low calcium tetany; with vitamin D for hypocalcemia |
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Term
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Definition
(etidronate, alendronate, pamidronate, ibandronate, zoledronic acid)
Uses: Paget’s disease (slows bone turnover), osteoporosis (prevention, treatment)
they have strong affinity for bone.
MOA: decreases osteoclastic activity (block). Direct inhibition of bone reabsorption. Remain in the bone matrix until the bone is remodeled and then are released.
Advantages: - (over calcitonin & PTH) oral efficacy, lack of antigenicity, lower cost, long-acting formulations
-Available with vitamin D (FOSAMAX PLUS D) Vitamin Dincreases absorption of calcium from the diet |
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Term
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Definition
use: osteoperosis
MOA: decrease osteoclastic activity |
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Term
| Selective Estrogen Receptor Modulators (SERMS) |
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Definition
Raloxifene
MOA: decreases bone resorption (estrogen agonist on bone)
Estradiol is useful for the treatment of osteoporosis
Estradiol and raloxifene decrease bone resorption |
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Term
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Definition
Uses: hypercalcemia (chelating agent)
-reduces calcium resorption
-reduces plasma Ca++ levels by increasing excretion
Adverse reactions: rarely used because of potential toxicity |
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Term
| Glucocorticoids (Prednisone) |
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Definition
Uses – hypercalcemia (increases Ca++ excretion)
Uses – hypercalcemia |
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Term
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Definition
Uses – 2° Hyperparathroidism (kidney disease) (not very common)
MOA: - ↑ sensitivity of Ca++-sensing receptors → ↓ PTH |
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Term
| hyperparthyroidism symptoms: |
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Definition
hypercalcemia, hypercalcuria, kidney stones (precipitation of excess calcium), skeletal abnormalities, muscle weakness, gastrointestinal problems, neurologic problems
Treatment: usually surgery |
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Term
| hypoparathyroidism symptoms and treatments: |
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Definition
Symptoms: hypocalcemia, tetany, convulsions, muscle spasms Treatment: dietary calcium supplements plus vitamin D (or 1,25-OH-vitamin D) |
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Term
| Pseudohypoparathyroidism cause, symptoms and treatment: |
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Definition
Cause: tissue insensitivity to PTH
Symptoms: hypocalcemia
Treatment: vitamin D + calcium |
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Term
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Definition
Vitamin D Deficiencies:
Cause: dietary deficiency, absorption problems, liver disease, kidney dysfunction,
Symptoms: bone pain, skeletal deformities, fractures, mild hypocalcemia,
Treatment: vitamin D (or 1,25-OH-vitamin D) |
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Term
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Definition
Cause: ingestion of large doses
Symptoms: hypercalcemia, soft tissue calcification (no bone demineralization)
Treatment: cessation of vitamin D administration, glucocorticoids |
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Term
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Definition
An autoimmun edisease that destroys bone. (causes bone resorption)
first we can use calcitonin (sitmulates calcium reabsorption) and at the same time we can treat these patients bisphosphonates (blocks calcium efflux from the bone)
Cause: increased bone resorption
Symptoms: bone pain, fractures
Treatment: calcitonin, bisphosphonates (infusion of zoledronic acid → 1 year efficacy) |
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Term
| Sprue (celiac disease), Crohn’s Disease, Cirrhosis |
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Definition
Treatment: vitamin D + Ca++
diseases that affect the absorption of food and calcium leading to osteomalacia : the mineralization of the new bone is very weak
Vitamin D can not stimulate the absorption of calcium
Cause: decreased vitamin D absorption |
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Term
| Osteoporosis (postmenopausal) |
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Definition
Causes: aging (↓ estrogen or androgen), endocrinopathies, glucocorticoids: Inhibition of Estrogens, GI absorption of calcium.
Symptoms: fractures
Treatment: calcium supplementation, vitamin D, estrogens, SERMS, calcitonin, biphosphonates, PTH |
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Term
| Severe Hypercalcemia (life-threatening) |
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Definition
High levels of calcium that can induce heart failure, coma, etc.
Treatment: IV hydration and diuretic, EDTA (chelating agent), calcitonin, glucocorticoids (decreases bone resorption of calcium and intestinal calcium absorption and increases renal calcium excretion |
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Term
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Definition
| can help lower calcium levels in plasma |
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