title: Percoll purification of chromaffin granules inhibits their ability to take up and maintain calcium.
abstract: Secretory granules of the adrenal medulla have recently been shown to be able to sequester and release Ca2+, in addition to their previously established role as carriers of secretory products. In order to study the ability of these or any other secretory granules to participate in intracellular calcium homeostasis, it is imperative that they should be free of other contaminating Ca2+ sequestering organelles, and that the Ca2+ uptake and release mechanisms of those granules should remain intact throughout any chosen purification procedure. We report here that chromaffin granules which were purified by the isopycnic gradient medium Percoll, or even incubated with it, showed an attenuated ability to sequester Ca2+.
authors.affiliation: Department of Medical Biochemistry, University of Calgary Medical Sciences Centre, Alba, Canada.
authors.forename: P G
authors.initials: PG
authors.lastname: Jones
authors.forename: J
authors.initials: J
authors.lastname: Meneses
authors.forename: D M
authors.initials: DM
authors.lastname: Waisman
mesh_terms: D000311:Adrenal Glands / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002469:Cell Separation; D002499:Centrifugation, Density Gradient; D002837:Chromaffin Granules / Q000187:drug effects* / Q000378:metabolism; D011205:Povidone / Q000494:pharmacology*; D012822:Silicon Dioxide / Q000494:pharmacology*
chemical_list: C016039:Percoll; D012822:Silicon Dioxide; D011205:Povidone; D002118:Calcium