| Theme |
Progress in parathyroid research : Pathophysiology and treatment |
| Title |
Classic target organs of parathyroid hormone |
| Author |
Junichiro James Kazama |
Department of Nephrology and Hypertension, Fukushima Medical University |
| [ Summary ] |
The classic target organs of the parathyroid hormone (PTH) are kidney and bone. PTH promotes paracellular Ca reabsorption in the ascending limb of Henle and transcellular Ca reabsorption from the distal convoluted tubule to the connecting tubule. PTH inhibits phosphate reabsorption and activates CYP27B1 in the proximal tubules. It induces bone resorption through osteoblastic actions. For osteocytes, its continuous action promotes osteoclast formation while its intermittent action promotes bone formation. The essence of various PTH actions is "prevention of decreased Ca concentration in extracellular fluid". |