Regulation Of Intracellular Calcium Homeostasis In Trypanosoma Cruzi. Effects Of Calmidazolium And Trifluoperazine.

dc.creatorVercesi, A E
dc.creatorHoffmann, M E
dc.creatorBernardes, C F
dc.creatorDocampo, R
dc.date1991-May
dc.date2015-11-27T12:19:22Z
dc.date2015-11-27T12:19:22Z
dc.date.accessioned2018-03-29T00:53:04Z
dc.date.available2018-03-29T00:53:04Z
dc.identifierCell Calcium. v. 12, n. 5, p. 361-9, 1991-May.
dc.identifier0143-4160
dc.identifier
dc.identifierhttp://www.ncbi.nlm.nih.gov/pubmed/1893396
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/194246
dc.identifier1893396
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1294479
dc.descriptionTrypanosoma cruzi epimastigotes maintained an intracellular free calcium concentration of about 0.15 microM, as measured with the fluorescent indicator Fura-2. The maintenance of low [Ca2+]i is energy-dependent since it is disrupted by KCN and FCCP. When the cells were permeabilized with digitonin, the steady-state free Ca2+ concentration in the absence of ATP was about 0.7 microM. The additional presence of ATP resulted in a steady-state level close to 0.1-0.2 microM which compares favorably with the concentration detected in intact cells. Intracellular Ca2+ uptake at high levels of free Ca2+ (greater than 1 microM) was due to energy-dependent mitochondrial uptake as indicated by its FCCP-sensitivity. However, as the free Ca2+ concentration was lowered from 1 microM, essentially all uptake was due to the ATP-dependent Ca2+ sequestration by the endoplasmic reticulum as indicated by its stimulation by ATP, and its inhibition by sodium vanadate. High concentrations of the calmodulin antagonist trifluoperazine, inhibited both the Ca2+ uptake by the endoplasmic reticulum and by the mitochondria, while calmidazolium released Ca2+ from both compartments. In addition, trifluoperazine and calmidazolium inhibited respiration and collapsed the mitochondrial membrane potential of T. cruzi, thus indicating non-specific effects unrelated to calmodulin.
dc.description12
dc.description361-9
dc.languageeng
dc.relationCell Calcium
dc.relationCell Calcium
dc.rightsfechado
dc.rights
dc.sourcePubMed
dc.subjectAnimals
dc.subjectBiological Transport
dc.subjectCalcium
dc.subjectCalmodulin
dc.subjectCell Membrane Permeability
dc.subjectCytosol
dc.subjectHomeostasis
dc.subjectImidazoles
dc.subjectMembrane Potentials
dc.subjectOxygen
dc.subjectSpectrometry, Fluorescence
dc.subjectTrifluoperazine
dc.subjectTrypanosoma Cruzi
dc.titleRegulation Of Intracellular Calcium Homeostasis In Trypanosoma Cruzi. Effects Of Calmidazolium And Trifluoperazine.
dc.typeArtículos de revistas


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