[New insights on plasma phosphate and calcium control].
The physiological regulation of renal Pi reabsorption is mediated by renal type II Na/Pi cotransporters. The type II a transporter is a key player of renal Pi reabsorption and regulated, among other factors, by parathyroid hormone (PTH). The PTH-induced inhibition of Pi reabsorption is mediated by endocytosis of the type II a transporter from the brush-border membrane and subsequent lysosomal degradation. In addition, during weaning, the type II c Na/Pi cotransporter (growth related Na/Pi cotransporter) is induced in the apical membrane of proximal tubular cells. The type II c transporter is also regulated by PTH, FGF-23 and PHEX. Studying the mechanisms of the regulation of type II c transporters by PHEX and FGF-23 has increased understanding of the control of proximal tubular Pi handling and bone mineralization.
Segawa
Hiroko
H
Department of Molecular Nutrition, Institute of Health Biosciences, the University of Tokushima Graduate School.
Miyamoto
Kenichi
K
D000818:Animals; D002113:Calcification, Physiologic / Q000235:genetics*; D002118:Calcium / Q000097:blood*; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000502:physiology; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000378:metabolism; D053402:PHEX Phosphate Regulating Neutral Endopeptidase; D010281:Parathyroid Hormone / Q000502:physiology; D010758:Phosphorus / Q000097:blood*; D011506:Proteins / Q000502:physiology; D050608:Sodium-Phosphate Cotransporter Proteins; D050610:Sodium-Phosphate Cotransporter Proteins, Type II; D027981:Symporters / Q000145:classification / Q000502:physiology*
C000717427:FGF23 protein, human; D010281:Parathyroid Hormone; D011506:Proteins; D050608:Sodium-Phosphate Cotransporter Proteins; D050610:Sodium-Phosphate Cotransporter Proteins, Type II; D027981:Symporters; D010758:Phosphorus; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; D053402:PHEX Phosphate Regulating Neutral Endopeptidase; C506231:PHEX protein, human; D002118:Calcium