?[3]

PTH enhances calcium absorption from the bone through two mechanisms.It is noteworthy that mature osteoclasts do not have receptors for parathyroid hormone (PTH); they are stimulated to activate and grow by cytokines from activated osteoblasts and osteocytes, or by immature osteoclast precursors with PTH and vitamin D receptors undergoing differentiation.[3]Kidney function involves PTH inhibiting phosphate reabsorption in the proximal tubule and enhancing calcium reabsorption in the ascending loop of Henle, distal tubule, and collecting tubule.When the parathyroid hormone (PTH) attaches to receptors on these cells, the osteocytic membrane shifts calcium ions from the bone fluid to the extracellular fluid.