Contribution of the kinetics of G protein dissociation to the characteristic modifications of N-type calcium channel activity

Autor: Michel De Waard, Norbert Weiss, Anne Feltz, Christophe Arnoult
Přispěvatelé: Canaux calciques , fonctions et pathologies, Université Joseph Fourier - Grenoble 1 (UJF)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Laboratoire de Neurobiologie (UMR 8544) (NEURO), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Inserm, École normale supérieure - Paris (ENS-PSL)
Rok vydání: 2009
Předmět:
Patch-Clamp Techniques
Xenopus
Receptors
Opioid
mu
MESH: Rabbits
N-type calcium channel
MESH: Analgesics
Opioid
MESH: Microinjections
Membrane Potentials
MESH: Dose-Response Relationship
Drug
MESH: GTP-Binding Protein beta Subunits
Calcium Channels
N-Type
0302 clinical medicine
MESH: Animals
MESH: Xenopus
Membrane potential
0303 health sciences
Voltage-dependent calcium channel
Chemistry
General Neuroscience
GTP-Binding Protein beta Subunits
MESH: Electric Stimulation
General Medicine
Analgesics
Opioid
Biochemistry
[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]
Neurons and Cognition (q-bio.NC)
Rabbits
MESH: GTP-Binding Proteins
Microinjections
MESH: Rats
G protein
Models
Neurological
Kinetics
chemistry.chemical_element
MESH: Receptors
Opioid
mu
MESH: Enkephalin
Ala(2)-MePhe(4)-Gly(5)
[SDV.BC]Life Sciences [q-bio]/Cellular Biology
Calcium
MESH: Oocytes
03 medical and health sciences
GTP-Binding Proteins
MESH: Models
Neurological
MESH: Calcium Channels
N-Type
MESH: Patch-Clamp Techniques
MESH: Dose-Response Relationship
Radiation
Animals
MESH: Membrane Potentials
030304 developmental biology
G protein-coupled receptor
Dose-Response Relationship
Drug
Calcium channel
Dose-Response Relationship
Radiation
Enkephalin
Ala(2)-MePhe(4)-Gly(5)
Electric Stimulation
Rats
Quantitative Biology - Neurons and Cognition
FOS: Biological sciences
Oocytes
Biophysics
030217 neurology & neurosurgery
Zdroj: Neuroscience Research
Neuroscience Research, Elsevier, 2006, 56 (3), pp.332-43. ⟨10.1016/j.neures.2006.08.002⟩
Neuroscience Research, 2006, 56 (3), pp.332-43. ⟨10.1016/j.neures.2006.08.002⟩
ISSN: 0168-0102
1872-8111
DOI: 10.48550/arxiv.0911.1844
Popis: Direct G protein inhibition of N-type calcium channels is recognized by characteristic biophysical modifications. In this study, we quantify and simulate the importance of G protein dissociation on the phenotype of G protein-regulated whole-cell currents. Based on the observation that the voltage-dependence of the time constant of recovery from G protein inhibition is correlated with the voltage-dependence of channel opening, we depict all G protein effects by a simple kinetic scheme. All landmark modifications in calcium currents, except inhibition, can be successfully described using three simple biophysical parameters (extent of block, extent of recovery, and time constant of recovery). Modifications of these parameters by auxiliary β subunits are at the origin of differences in N-type channel regulation by G proteins. The simulation data illustrate that channel reluctance can occur as the result of an experimental bias linked to the variable extent of G protein dissociation when peak currents are measured at various membrane potentials. To produce alterations in channel kinetics, the two most important parameters are the extents of initial block and recovery. These data emphasize the contribution of the degree and kinetics of G protein dissociation in the modification of N-type currents.
Databáze: OpenAIRE
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