Coordinate regulation of rat renal parathyroid hormone receptor mRNA and Na-Pi cotransporter mRNA and protein
Kilav, R.; Silver, J.; Biber, J.; Murer, H.; Naveh-Many, T.
American Journal of Physiology 268(6 Pt 2): F1017-F1022
1995
ISSN/ISBN: 0002-9513 PMID: 7611444 Document Number: 445631
Parathyroid hormone (PTH) acts on the kidney by binding to the PTH receptor, leading to a decrease in the active renal reabsorption of phosphate by the Na-P-i cotransporter, which is also independently activated by hypophosphatemia. We have studied the effects of hypo- and hyperparathyroidism and hypophosphatemia on PTH receptor mRNA and Na-P-i cotransporter mRNA and protein. Both surgical parathyroidectomy and hypophosphatemia, which itself leads to hypoparathyroidism, led to an upregulation of the PTH receptor mRNA and Na-P-i cotransporter mRNA and protein. Parathyroidectomized rats fed a low-P-i diet had an increase in PTH receptor and Na-P-i cotransporter mRNAs. Diet-induced hyperparathyroidism had no effect on PTH receptor mRNA and Na-P-i cotransporter mRNA and protein. The effect of hypoparathyroidism and hypophosphatemia to increase both PTH receptor mRNA and Na-P-i cotransporter mRNA and protein shows that there is a tight coordinate regulation of these factors, which are both involved in PTH action.