title: Renal handling of calcium.
abstract: Ca absorption is mediated by both active and passive processes. Absorption in both proximal tubule and thick ascending limb is mainly coupled indirectly to Na absorption and is a passive process through the paracellular pathway. In the distal convoluted tubule, Ca absorption is regulated independently of Na absorption; this is the principal site of action of parathyroid hormone, calcitonin, and 1,25-(OH)2D3. Models for transport in proximal tubule, thick ascending limb, and distal convoluted tubule afford attractive explanations for the influence on Ca transport of effective arterial blood volume, parathyroid hormone, acid-base balance, genetic disturbances such as Bartter's and Gitelman's syndromes, and diuretic action.
authors.affiliation: Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Tex. 75235, USA.
authors.forename: D W
authors.initials: DW
authors.lastname: Seldin
mesh_terms: D002118:Calcium / Q000378:metabolism*; D006801:Humans; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*
chemical_list: D002118:Calcium