In chronic kidney disease, why does increased parathyroid hormone (PTH) secretion accelerate vascular calcification, even with phosphate binders?

💡 Explanation

PTH increases intracellular calcium levels via cAMP and IP3 pathways in vascular smooth muscle cells, leading to calcification because this effect is independent of phosphate levels; therefore, vascular calcification proceeds even if phosphate is controlled, rather than PTH directly depositing calcium or binders perfectly normalizing phosphate.

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