Calcium Homeostasis Flashcards
Important roles of Ca2+
intracellular signaling in all cells, normal excitability of neurons and all types of muscle; structural functions
What are the 3 pools of Ca2+ ions
intraceullar, extracellular, bone matrix
Where are the majority of Ca ion stored?
bone
Osteoblasts and Ca homeostasis
bone matrix deposition
brings calcium into bone
Osteoclasts
bone breakdown
release Ca2+ into the blood
-sorpt
into blood or plasma
What is the role of calcitonin in calcium homeostasis?
takes Ca2+ out of the ECF and brings it into bone; released with plasma Ca2+ is high
decreases bone resorption
What is the role of parathyroid hormone in calcium homeostasis?
releases Ca2+ from bone and into the ECF; increases calcium levels; released when plasma Ca2+ is low; enhances renal reabsorption of Ca2+; stimulates calcitrol release
what is the function of calcitriol?
increases intestinal absorption
what secretes calcitonin
parafollicular cells
what secretes PTH?
chief cells
what happens in bone remodeling
osteoclast breakdown the bone and then osteoblast make new bone
What is Wolff’s Law?
bone adapts to pressure, or the lack thereof
