PTH role on phosphate levels

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str8cashhomie

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The PTH stimulates bone resorption of calcium and phosphate, yet the kidney reabsorbs calcium at the
DCT but decreases reabsorption at PCT. Also, 1,25 OH2 D3 increases absorption of Calcium and phosphate in the gut. This seems contradictory, can anyone explain what role phosphate has in bone homeostasis and what would cause it to be elevated in the blood?

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PTH decreases phosphate reabsorption in the KIDNEYS (by increasing cAMP) --> decreased phosphate serum levels --> increases serum free Ca2+ (because phosphate binds Ca2+ and decreases its serum levels)
1,25 VitD increases calcium AND phosphate reabsorption --> phosphate is needed to build bone

This is just off the top of my head, feel free to correct me
 
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