A family of calcium-permeable channels in the kidney: distinct roles in renal calcium handling.
OBJECTIVE
Calcium is an essential intracellular messenger and a major component of the mineral phase of the skeleton. Calcium is absorbed in the intestine and reabsorbed in the kidney. The underlying transepithelial calcium transport mechanisms play crucial roles in calcium homeostasis. In this review, we present new developments in the area of calcium transport at the apical membrane, the first step in transepithelial calcium transport.


RESULTS
Recently, a group of transient receptor potential (TRP)-related calcium-permeable channels has been identified. Several of these channels serve as important epithelial calcium entry mechanisms and possibly also as osmolarity sensors.


CONCLUSIONS
Calcium channels in the kidney play important roles in maintaining total body calcium homeostasis. Their dysfunction may be associated with several human diseases such as hypercaliuric nephrolithiasis, certain forms of osteoporosis, Gitelman's disease and Bartter's syndrome.
Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA. jpeng@rics.bwh.harvard.edu
Ji-Bin
JB
Peng
Matthias A
MA
Hediger
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism*; D027682:Cation Transport Proteins; D002412:Cations / Q000378:metabolism; D006801:Humans; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D050916:TRPV Cation Channels; D014807:Vitamin D / Q000494:pharmacology
D015220:Calcium Channels; D027682:Cation Transport Proteins; D002412:Cations; D007473:Ion Channels; D050916:TRPV Cation Channels; C416986:TRPV4 protein, human; C492239:TRPV5 protein, human; C120776:TRPV6 channel; D014807:Vitamin D; D002118:Calcium