title: TRPV5 and TRPV6 in Ca(2+) (re)absorption: regulating Ca(2+) entry at the gate.
abstract: Many physiological functions rely on the exact maintenance of body Ca(2+) balance. Therefore, the extracellular Ca(2+) concentration is tightly regulated by the concerted actions of intestinal Ca(2+) absorption, exchange of Ca(2+) to and from bone, and renal Ca(2+) reabsorption. Renal distal convoluted and connecting tubular cells as well as duodenal epithelial cells are unique in their ability to mediate transcellular (re)absorption of Ca(2+) at large and highly variable rates. Two members of the transient receptor potential (TRP) superfamily, TRP vanilloid (TRPV)5 and TRPV6, are specialized epithelial Ca(2+) channels responsible for the critical Ca(2+) entry step in transcellular Ca(2+) (re)absorption in intestine and kidney, respectively. Because transcellular Ca(2+) transport is fine-tuned to the body's specific requirements, regulation of the transmembrane Ca(2+) flux through TRPV5/6 is of particular importance and has, therefore, to be conspicuously controlled. We present an overview of the current knowledge and recent advances concerning the coordinated regulation of Ca(2+) influx through the epithelial Ca(2+) channels TRPV5 and TRPV6 in transcellular Ca(2+) (re)absorption.
authors.affiliation: Department of Physiology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
authors.forename: Tom
authors.initials: T
authors.lastname: Nijenhuis
authors.forename: Joost G J
authors.initials: JG
authors.lastname: Hoenderop
authors.forename: René J M
authors.initials: RJ
authors.lastname: Bindels
mesh_terms: D000728:Androgens / Q000494:pharmacology; D000818:Animals; D017306:Annexin A2 / Q000502:physiology; D002117:Calcitriol / Q000502:physiology; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000502:physiology*; D002135:Calcium-Binding Proteins; D002147:Calmodulin / Q000494:pharmacology; D003598:Cytoskeletal Proteins / Q000502:physiology; D004032:Diet; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D004967:Estrogens / Q000494:pharmacology; D025461:Feedback, Physiological; D005959:Glucosidases; D006801:Humans; D006863:Hydrogen-Ion Concentration; D017874:Immediate-Early Proteins / Q000502:physiology; D007166:Immunosuppressive Agents / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D010281:Parathyroid Hormone / Q000502:physiology; D010750:Phosphoproteins / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D020836:Protein Structure, Quaternary; D009418:S100 Proteins / Q000502:physiology; D049993:Sodium Chloride Symporter Inhibitors / Q000494:pharmacology; D017923:Sodium-Hydrogen Exchangers; D050916:TRPV Cation Channels / Q000502:physiology*; D000099184:Serum-Glucocorticoid Regulated Kinases; D000099248:S100 Calcium Binding Protein A10
chemical_list: D000728:Androgens; D017306:Annexin A2; D002117:Calcitriol; D002118:Calcium; D015220:Calcium Channels; D002135:Calcium-Binding Proteins; D002147:Calmodulin; D003598:Cytoskeletal Proteins; D004967:Estrogens; D005959:Glucosidases; D017874:Immediate-Early Proteins; D007166:Immunosuppressive Agents; D047908:Intracellular Signaling Peptides and Proteins; D010281:Parathyroid Hormone; D010750:Phosphoproteins; D017346:Protein Serine-Threonine Kinases; D009418:S100 Proteins; D049993:Sodium Chloride Symporter Inhibitors; D017923:Sodium-Hydrogen Exchangers; D050916:TRPV Cation Channels; D000099184:Serum-Glucocorticoid Regulated Kinases; D000099248:S100 Calcium Binding Protein A10; C472822:ANXA2 protein, human; C512949:Prkcsh protein, mouse; C492239:TRPV5 protein, human; C120776:TRPV6 channel; C093376:sodium-hydrogen exchanger regulatory factor; C070368:PRKCSH protein, human