title: Calcium Uptake in Crude Tissue Preparation.
abstract: The various isoforms of the sarco/endoplasmic reticulum Ca(2+) ATPase (SERCA) are responsible for the Ca(2+) uptake from the cytosol into the endoplasmic or sarcoplasmic reticulum (ER/SR). In some tissues, the activity of SERCA can be modulated by binding partners, such as phospholamban and sarcolipin. The activity of SERCA can be characterized by its apparent affinity for Ca(2+) as well as maximal enzymatic velocity. Both parameters can be effectively determined by the protocol described here. Specifically, we describe the measurement of the rate of oxalate-facilitated (45)Ca uptake into the SR of crude mouse ventricular homogenates. This protocol can easily be adapted for different tissues and animal models as well as cultured cells.
authors.affiliation: Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Bidwell
authors.affiliation: Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH, 45267-0575, USA. litsa.kranias@uc.edu.
authors.forename: Evangelia G
authors.initials: EG
authors.lastname: Kranias
mesh_terms: D000818:Animals; D002118:Calcium / Q000737:chemistry* / Q000378:metabolism; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000737:chemistry / Q000378:metabolism; D051379:Mice; D009124:Muscle Proteins / Q000737:chemistry; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism; D011510:Proteolipids / Q000737:chemistry; D012519:Sarcoplasmic Reticulum / Q000737:chemistry / Q000378:metabolism; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D009124:Muscle Proteins; D011510:Proteolipids; C077258:sarcolipin; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D002118:Calcium
keywords: 45Ca; Calcium affinity; Calcium uptake; K m; Oxalate; Phospholamban; SERCA; Sarcolipin; V max