Consulta: creatorFacets:"HIDALGO,CECILIA"
Registros recuperados: 7
Data/hora: 04/06/2024 06:36:51

Redox regulation of RyR-mediated Ca2+ release in muscle and neurons
Provedor de dados: Biological Research
Autores: HIDALGO,CECILIA; BULL,RICARDO; BEHRENS,M. ISABEL; DONOSO,PAULINA.
Changes in the redox state of the intracellular ryanodine receptor/Ca2+ release channels of skeletal and cardiac muscle or brain cortex neurons affect their activity. In particular, agents that oxidize or alkylate free SH residues of the channel protein strongly enhance Ca2+-induced Ca2+ release, whereas reducing agents have the opposite effects. We will discuss here how modifications of highly reactive cysteine residues by endogenous redox agents or cellular redox state influence RyR channel activation by Ca2+ and ATP or inhibition by Mg2+. Possible physiological and pathological implications of these results on cellular Ca2+ signaling will be addressed as well.
Tipo: Journal article
Palavras-chave: Redox state; Ryanodine receptors; Sarcoplasmic/endoplasmic reticulum; Calcium release; S-nitrosylation; S-glutathionylation.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000400007

UNA CONVERSACION CON EL DR. MARIO LUXORO MARIANI: PREMIO NACIONAL DE CIENCIAS NATURALES, AÑO 2000
Provedor de dados: Biological Research
Autores: HIDALGO,CECILIA.
Tipo: Journal article
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000200002

SH Oxidation Stimulates Calcium Release Channels (Ryanodine Receptors) From Excitable Cells
Provedor de dados: Biological Research
Autores: HIDALGO,CECILIA; BULL,RICARDO; MARENGO,JUAN J; PÉREZ,CLAUDIO F; DONOSO,PAULINA.
The effects of redox reagents on the activity of the intracellular calcium release channels (ryanodine receptors) of skeletal and cardiac muscle, or brain cortex neurons, was examined. In lipid bilayer experiments, oxidizing agents (2,2'-dithiodipyridine or thimerosal) modified the calcium dependence of all single channels studied. After controlled oxidation channels became active at sub &amp;micro;M calcium concentrations and were not inhibited by increasing the calcium concentration to 0.5 mM. Subsequent reduction reversed these effects. Channels purified from amphibian skeletal muscle exhibited the same behavior, indicating that the SH groups responsible for modifying the calcium dependence belong to the channel protein. Parallel experiments that...
Tipo: Journal article
Palavras-chave: Calcium dependence; Neurons; Redox state; Ryanodine receptors; Sarcoplasmic reticulum; Skeletal and cardiac muscle.
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000200011

Effect of iron on the activation of the MAPK/ERK pathway in PC12 neuroblastoma cells
Provedor de dados: Biological Research
Autores: MUÑOZ,PABLO; ZAVALA,GABRIELA; CASTILLO,KAREN; AGUIRRE,PABLA; HIDALGO,CECILIA; NÚÑEZ,MARCO T.
Recent evidence suggests that reactive oxygen species function as second messenger molecules in normal physiological processes. For example, activation of N-Methyl-D-Aspartate receptor results in the production of ROS, which appears to be critical for synaptic plasticity, one of the cellular mechanisms that underlie learning and memory. In this work, we studied the effect of iron in the activation of MAPK/ERK pathway and on Ca2+ signaling in neuronal PC12 cells. We found that iron-dependent generation of hydroxyl radicals is likely to modulate Ca2+ signaling through RyR calcium channel activation, which, in turn, activates the MAPK/ERK pathway. These findings underline the relevance of iron in normal neuronal function.
Tipo: Journal article
Palavras-chave: NMDA receptor; Calcium; Iron; Oxidative stress; MAPK/ERK; Hippocampal slices; Long-term potentiation.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100021

Redox regulation of calcium release in skeletal and cardiac muscle
Provedor de dados: Biological Research
Autores: HIDALGO,CECILIA; ARACENA,PAULA; SANCHEZ,GINA; DONOSO,PAULINA.
In skeletal and cardiac muscle cells, specific isoforms of the Ryanodine receptor channels mediate Ca2+ release from the sarcoplasmic reticulum. These channels are highly susceptible to redox modifications, which regulate channel activity. In this work, we studied the effects of Ca2+ (endogenous agonist) and Mg2+ (endogenous inhibitor) on the kinetics of Ca2+ release from sarcoplasmic reticulum vesicles isolated from skeletal or cardiac mammalian muscle. Native skeletal vesicles exhibited maximal stimulation of release kinetics by 10-20 µM [Ca2+], whereas in native cardiac vesicles, maximal stimulation of release required only 1 µM [Ca2+]. In 10 µM [Ca2+], free [Mg2+] &lt; 0.1 mM produced marked inhibition of release from skeletal vesicles but free [Mg2+]...
Tipo: Journal article
Palavras-chave: Redox state; Ryanodine receptors; Sarcoplasmic reticulum; Calcium release kinetics; Mg2+ inhibition; S-nitrosoglutathione.
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000200009

Signal transduction and gene expression regulated by calcium release from internal stores in excitable cells
Provedor de dados: Biological Research
Autores: CARRASCO,MARÍA ANGÉLICA; JAIMOVICH,ENRIQUE; KEMMERLING,ULRIKE; HIDALGO,CECILIA.
Calcium regulation of several transcription factors involves different calcium-dependent signaling cascades and engages cytoplasmic as well as nuclear calcium signals. The study of the specific sources of calcium signals involved in regulation of gene expression in skeletal muscle has been addressed only recently. In this tissue, most cytoplasmic and nuclear calcium signals originate from calcium release from internal stores, mediated either by ryanodine receptor (RyR) or IP3 receptor (IP3R) channels. The latter are located both in the sarcoplasmic reticulum (SR) and in the nuclear membrane, and their activation results in long-lasting nuclear calcium increase. The calcium signals mediated by RyR and IP3R are very different in kinetics, amplitude and...
Tipo: Journal article
Palavras-chave: Calcium signals; Intracellular stores; Transcription; Oxidation; Neurons; Skeletal muscle.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000400028

Fast kinetics of calcium dissociation from calsequestrin
Provedor de dados: Biological Research
Autores: BELTRÁN,MARIANELA; BARRIENTOS,GENARO; HIDALGO,CECILIA.
We measured the kinetics of calcium dissociation from calsequestrin in solution or forming part of isolated junctional sarcoplasmic reticulum membranes by mixing calsequestrin equilibrated with calcium with calcium-free solutions in a stopped-flow system. In parallel, we measured the kinetics of the intrinsic fluorescence changes that take place following calcium dissociation from calsequestrin. We found that at 25ºC calcium dissociation was 10-fold faster for calsequestrin attached to junctional membranes (k = 109 s-1) than in solution. These results imply that calcium dissociation from calsequestrin in vivo is not rate limiting during excitation-contraction coupling. In addition, we found that the intrinsic fluorescence decrease for calsequestrin in...
Tipo: Journal article
Palavras-chave: Calcium-binding proteins; Ryanodine receptors; Sarcoplasmic reticulum; Calcium release kinetics; Excitation-contraction coupling; Skeletal and cardiac muscle.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000300011