Term
|
Definition
| growth and development of endochondral bone |
|
|
Term
| define remodeling, when does it occur |
|
Definition
continoous process of breakdown and renewal
final option after linear growth in finished |
|
|
Term
| what are the three steps in remodeling |
|
Definition
IL-1 and IL-6 released from osteoblast stimulate osteoclast to reabsorb tunnels in corticoid bone or scallops in trabecular bone
osteoclasts replaces bone areas with collagen, osteocalcin, and protein
mineralization occurs after osteoblasts achieve 20 microns of thickness |
|
|
Term
| what are three problems with bone remodeling |
|
Definition
deficits occur after each cycle
deficits increase with age
can never get back to origional bone mass after remodel |
|
|
Term
| what three things can alter remodeling |
|
Definition
|
|
Term
| what hormones alter remodeling (5) |
|
Definition
thyroid
PTH
vitamin D
glucocorticoids
estrogen |
|
|
Term
|
Definition
neuron excitability
neurotransmitter release
muscle contraction
membrane integrity
blood coagulation
secondary messenger for hormones |
|
|
Term
|
Definition
| skeleton in a pool exchangable with interstitial fluid |
|
|
Term
| what is stored in bone (5) |
|
Definition
|
|
Term
|
Definition
75% is from dairy intake
adults 45-50 yo should have supplement with vitamin D |
|
|
Term
| how does Ca get into the body |
|
Definition
| facilitated diffusion through SI |
|
|
Term
|
Definition
inversly proportional to intake
(not as good as we age) |
|
|
Term
| where and how much Ca is excreted |
|
Definition
150mg is loss via billiary and intestinal sloughing
9mg is secreted in kidney but 98% is reabsorbed |
|
|
Term
| what do loop diruetics do to Ca excretion |
|
Definition
| act on ascending limg to cause increased Ca loss (but its a better diruetic) |
|
|
Term
| what do thiazida diruetics do to Ca excretion |
|
Definition
| uncouple Na and Ca excretion causing reduced Ca loss |
|
|
Term
| where is phosphate located in the body |
|
Definition
80% in bone
15% in soft tissue |
|
|
Term
| what are 5 functions of phosphate |
|
Definition
membrane phospholipids
modifies Ca
role in renal H excretion
secondary messenger
energy metabolism |
|
|
Term
| where, how, and how much phosphate is absorbed in the gut |
|
Definition
active transport and vit D stimulate absorption
2/3 is absorbed |
|
|
Term
| where is phosphate is excreted, how much |
|
Definition
excreted in urine
80% is reabsorbed |
|
|
Term
|
Definition
| prehormone is cleaved in ER and in golgi it makes PTH which lives in secretory granules until secreted. if not secreted soon enough they undergo proteolysis and the gland gets hypertrophy and hyperplasia |
|
|
Term
| what is the half life of PTH |
|
Definition
|
|
Term
| how does PTH act on target cells |
|
Definition
|
|
Term
| what are the functions of PTH (4) |
|
Definition
increase Ca and P absorption in intestines by activating vitamin D
increase bone reabsorption bia osteoblast action on osteoclast
increase Ca reabsorption in kidney
inhibit kidney phosphate reabsorption |
|
|
Term
|
Definition
| parafollicular C cells in thyroid release it when plasma Ca is high |
|
|
Term
| what are the two actions of calcitonin |
|
Definition
inhibition of osteoclast bone reabsorption
increased urinary Ca and P excretion |
|
|
Term
| what are the two types of viramin D and where are they made |
|
Definition
D2: yeast
D3: animals and higher plants |
|
|
Term
|
Definition
| in the bodycholesterol is reduced and is converted by UV into D3 hich is procesed in liver to calcifediol and then to calcitrol in kidney |
|
|
Term
| what are 4 pieces of evidence suggesting vitamin D is a hormone |
|
Definition
made in body in skin
not needed in diet (in theory)
transported in blood to distant sites
specific receptors in target tissues on DNA |
|
|
Term
| how does vitamin D affect the body |
|
Definition
increases absorption of P and Ca in SI
increases mobalization of P and Ca from bone with PTH help
decreases P and Ca excretion in kidney |
|
|
Term
|
Definition
| prehormone is cleaved in ER and in golgi it makes PTH which lives in secretory granules until secreted. if not secreted soon enough they undergo proteolysis and the gland gets hypertrophy and hyperplasia |
|
|
Term
| what is the half life of PTH |
|
Definition
|
|
Term
| how does PTH act on target cells |
|
Definition
|
|
Term
| what are the functions of PTH (4) |
|
Definition
increase Ca and P absorption in intestines by activating vitamin D
increase bone reabsorption bia osteoblast action on osteoclast
increase Ca reabsorption in kidney
inhibit kidney phosphate reabsorption |
|
|
Term
|
Definition
| parafollicular C cells in thyroid release it when plasma Ca is high |
|
|
Term
| what are the two actions of calcitonin |
|
Definition
inhibition of osteoclast bone reabsorption
increased urinary Ca and P excretion |
|
|
Term
| what are the two types of viramin D and where are they made |
|
Definition
D2: yeast
D3: animals and higher plants |
|
|
Term
|
Definition
| in the bodycholesterol is reduced and is converted by UV into D3 hich is procesed in liver to calcifediol and then to calcitrol in kidney |
|
|
Term
| what are 4 pieces of evidence suggesting vitamin D is a hormone |
|
Definition
made in body in skin
not needed in diet (in theory)
transported in blood to distant sites
specific receptors on DNA |
|
|
Term
| what are three things vitamin D does in the body |
|
Definition
absorption of Ca and P in SI
increase mobalization of Ca and P from bone with PTH help
decrease P and Ca excretion in kidney |
|
|
Term
| 5 symptoms of hypocalcemia |
|
Definition
parasthesia
increased neuromuscular excitability
laryngospasm
muscle cramps
tonic clonic convulsions |
|
|
Term
| 2 symptoms of hypercalcemia |
|
Definition
diverse clinical conditions
dehydration due to compormised renal concentration |
|
|
Term
| 4 symptoms of hypophosphatemia |
|
Definition
malaise
muscle weakness
osteomalacia
decreases RBC ATP and 2,3-BPG causing hemolytic anemia and impaired oxygenation - rare |
|
|
Term
| what are 4 causes of hypercalcemia |
|
Definition
increased intake of Ca in hypothyroid pt
familial benign hypercalcemia
vitamin D toxicity
milk alkali syndrome |
|
|
Term
| what is used to treat hypercalcemia |
|
Definition
calcitonin
IV bisphosphate
corticosteroids - vitamin D toxicity |
|
|
Term
| what is wrong in familial benign hypercalcemia |
|
Definition
| parathyroid cannot sense Ca so it increases PTH |
|
|
Term
| how can you get vitamin D toxicity |
|
Definition
| overuse of hyperparathyroid drugs |
|
|
Term
| what is used to treat vitamin D toxicity |
|
Definition
calcitonin
IV bisphosphate
corticosteroids |
|
|
Term
| what causes milk alkali syndrome |
|
Definition
| milk alkali powder increases Ca reabsption |
|
|
Term
| what are two conditions that cause hypercalcemia and hypophosphatemia |
|
Definition
hyperparathyroidism
PTH secreting tumor |
|
|
Term
| what is used to treat hypercalcemia and hypophosphatemia |
|
Definition
calcitonin
IV bisphosphate
IV/oral phosphate - hyperparathyroid
corticosteroids - PTH tumor |
|
|
Term
| how does hyperparathyroid cause problems, what are two complications |
|
Definition
increases PTH secretion
renal stones, peptic ulcers |
|
|
Term
| what type of cancer is a PTH secreting tumor |
|
Definition
| squamous or epithelial cell |
|
|
Term
| what is used to treat PTH secreting tumor |
|
Definition
calcitonin
IV bisphosphate
corticosteroids |
|
|
Term
| what is used to treat hyperparathyroidism |
|
Definition
calcitonin
IV bisphosphate
IV/oral phosphate |
|
|
Term
| what causes paget's disease, 6 symptoms |
|
Definition
excessive remodeling
weak, mishape, painful bones
deafness
cord compression
cardiac failure |
|
|
Term
| what is used to treat paget's disease |
|
Definition
calcitonin
IV bisphosphate |
|
|
Term
| what are two conditions that cause hypophosphatemia |
|
Definition
aluminum antacid toxicity
normal children: mild childhood anemia due to decreased affinity of Hb to O2 |
|
|
Term
| what is used to treat hypophosphatemia |
|
Definition
|
|
Term
| what three conditions can cause hypocalcemia and hypophosphatemia |
|
Definition
familial benign hypophosphatemia
rickets/osteomalacia
hypophosphatemia |
|
|
Term
| what is used to treat hypocalcemia and hypophosphatemia |
|
Definition
IV/oral phosphate
vitamin D - rickets/osteomalacia |
|
|
Term
| what is wrong in familial benign hypophosphatemia, what is a complication |
|
Definition
impaired vitamin D production causes increased PTH which depletes bone of Ca and P
causes dwarfism |
|
|
Term
|
Definition
| impaired vitamin D production causes increased PTH which deplates bone of Ca and P |
|
|
Term
| what are signs of rickets in kids (2) |
|
Definition
|
|
Term
| what are signs of rickets in adults |
|
Definition
painful bones
weak muscles |
|
|
Term
| what are three conditions that cause hypocalcemia and hyperphosphatemia |
|
Definition
hypoparathyroidism
pseudohypoparathyroidism
renal disease |
|
|
Term
| what is wrong in hypoparathyroidism , what is the cause |
|
Definition
| decreased release o f PTH due to thyroid or neck surgery, autoimmune or genetic disease |
|
|
Term
| how is hypoparathyroidism treated |
|
Definition
|
|
Term
| what is wrong in pseudohypoparathyroidism, what other symptoms are there |
|
Definition
body does not respond to PTH
short stature, metacarpals, metatarsals |
|
|
Term
| what is the treatment for pseudohypoparathyroidism |
|
Definition
|
|
Term
| what does renal disease do to Ca and P |
|
Definition
|
|
Term
| how do we treat the Ca and P effects of renal disease |
|
Definition
aluminum antacids
calcitriol |
|
|
Term
|
Definition
acts on osteoclast to inhibit bone reabsorption
rapid Ca reduction |
|
|
Term
|
Definition
| in hypercalcemia body will become sensitized in a few days |
|
|
Term
| what are 4 uses of calcitonin |
|
Definition
hypercalcemia
hypercalcemia + hyperphosphatemia
paget's disease
osteoperosis |
|
|
Term
| what are the 2 IV bisphosphates |
|
Definition
|
|
Term
| what is the MOA of IV bisphosphate |
|
Definition
inhibit osteoclast bone reabsorption
reduction of Ca over several days |
|
|
Term
| what 4 things for IV bisphosphates treat |
|
Definition
hypercalcemia
hypercalcemia + hyperphosphatemia
paget's disease
osteoperosis |
|
|
Term
|
Definition
| takes 1-2 days to reduce Ca |
|
|
Term
| what two things do corticosteroids treat |
|
Definition
lymphoma (PTH secreting tumor)
vitamin D toxicity caused hypercalcemmia |
|
|
Term
|
Definition
| increases plasma phosphate levels |
|
|
Term
| what are 3 side effects of IV/oral phosphate |
|
Definition
mild laxative
if not needed is rapidly excreted (no storage)
excess can reduce Ca via percipitation in soft tissue and be toxic |
|
|
Term
| 4 uses of IV/oral phosphate |
|
Definition
hypophosphatemia
hypocalcemia + hypophosphatemia
hyperparathyroidism
mild laxative |
|
|
Term
|
Definition
| supression of PTH decreases bone turn over |
|
|
Term
| side effects of vitamin D analogs |
|
Definition
| possible vitamin D toxicity |
|
|
Term
| 4 uses of vitamin D analogs |
|
Definition
rickets / osteomalacia
osteoperosis
treat hypoparathyroidism due to thyroid or parathyroid operation
renal failure 0 calcitrol |
|
|
Term
| what are the three types of vitamin D analogs and their administration |
|
Definition
ergocalciferol: oral, iv, im
dihydrotachysterol: oral
calcitrol: oral, iv |
|
|
Term
| what molecule is ergocalciferol |
|
Definition
|
|
Term
| what molecule is dihydrotachysterol |
|
Definition
|
|
Term
| what are the three types of Ca analogs and their administeration and why |
|
Definition
Ca chlorida: IV (IM causes vasodilation and burning)
Ca glyconate IV (IM causes abscess)
CA gluceptate IV or IM (IM causes some irritation) |
|
|
Term
| what are two uses of calcium analogs |
|
Definition
hypocalcemia + hyperphosphatemia
malabsorption or malnutrition of Ca |
|
|
Term
|
Definition
| decrease plasma phosphate by decreasing phosphate absorption |
|
|
Term
| aluminum antacids side effects |
|
Definition
|
|
Term
| aluminum antacids clinical use |
|
Definition
| clearance of phosphate in kidney failure |
|
|
Term
| define osteoperosis, who is it normally seen in |
|
Definition
| low bone mass and microfractures with minimal trauma in older women |
|
|
Term
| what are the types of osteoperosis |
|
Definition
primary type 1
primary type 2
secondary |
|
|
Term
| what is the cause of osteoperosis primary type 1 |
|
Definition
| loss of trabecular bone due to estrogen lack at menopause |
|
|
Term
| what is the cause of osteoperosis primary type 2 |
|
Definition
| loss of cortical and trabecular bone in men and women due to remodeling inefficiency, diet, activation of parathyroid axis with age |
|
|
Term
| what is the cause ot secondary osteoperosis |
|
Definition
systemic illness
medication: glucocorticoids, phenytoin |
|
|
Term
| what are the three regulators of bone density |
|
Definition
physical activity
endocrine status
Ca intake |
|
|
Term
| what is the trend in bone density over time |
|
Definition
| stable until 50 then progressivel decline |
|
|
Term
| what are 8 drugs that treat osteoperosis, state if they are for a specific kind or patient |
|
Definition
calcitonin
IV bisphosphate
vitamin D analogs
Ca carbonate
estrogen - post menopause osteoperosis
raloxifene
thiazide diruetuc
testosterone - hypogonadal males |
|
|
Term
| what is a side effect of Ca carbonate |
|
Definition
| constipation when >2000 mg/d |
|
|
Term
| what estrogen is used for osteperosis |
|
Definition
| conjugated equine estrogen without progesterone |
|
|
Term
| side effect of raloxifene |
|
Definition
| anti-estrogen in breast tissue |
|
|
Term
|
Definition
selective estradiol receptor modulator
agonist in liver and bone |
|
|
Term
| how do thiazidie diruetics help osteoperosis |
|
Definition
|
|
