How much afterhyperpolarization conductance is recruited by an action potential? A dynamic-clamp study in cat lumbar motoneurons
| Autor: | Marin Manuel, Daniel Zytnicki, Claude Meunier, Maud Donnet |
|---|---|
| Přispěvatelé: | Neurophysique et physiologie du système moteur (NPSM), Université Paris Descartes - Paris 5 (UPD5) - Centre National de la Recherche Scientifique (CNRS), Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
Models
Neurological Action Potentials MESH: Electric Conductivity Behavioral/Systems/Cognitive In Vitro Techniques MESH: Spinal Cord discharge properties 03 medical and health sciences MESH: Lumbar Vertebrae synaptic integration 0302 clinical medicine MESH: Models Neurological Reaction Time Animals MESH: Animals Single spike [SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] Reversal potential MESH: Action Potentials 030304 developmental biology Motor Neurons 0303 health sciences Entire population Lumbar Vertebrae MESH: Electrophysiology Chemistry Synaptic integration General Neuroscience Electric Conductivity Conductance MESH: Electric Stimulation spinal cord Afterhyperpolarization afterhyperpolarizing current Ih current Electric Stimulation MESH: Reaction Time Electrophysiology Decay time Clamp nervous system dynamic clamp Cats Biophysics [SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] MESH: Cats Neuroscience 030217 neurology & neurosurgery MESH: Motor Neurons |
| Zdroj: | Journal of Neuroscience Journal of Neuroscience, Society for Neuroscience, 2005, 25(39), pp.8917-23. 〈10.1523/JNEUROSCI.2154-05.2005〉 Journal of Neuroscience, Society for Neuroscience, 2005, 25 (39), pp.8917-23. ⟨10.1523/JNEUROSCI.2154-05.2005⟩ Journal of Neuroscience, Society for Neuroscience, 2005, 25(39), pp.8917-23. ⟨10.1523/JNEUROSCI.2154-05.2005⟩ Journal of Neuroscience, Society for Neuroscience, 2005, 25 (39), pp.8917-23. 〈10.1523/JNEUROSCI.2154-05.2005〉 |
| ISSN: | 0270-6474 1529-2401 |
| DOI: | 10.1523/JNEUROSCI.2154-05.2005〉 |
| Popis: | We accurately measured the conductance responsible for the afterhyperpolarization (medium AHP) that follows a single spike in spinal motoneurons of anesthetized cats. This was done by using the dynamic-clamp method. We injected an artificial current in the neurons that increased the AHP amplitude, and we made use of the fact that the intensity of the natural AHP current at the trough of the voltage trajectory was related linearly to the AHP amplitude. We determined at the same time the conductance and the reversal potential of the AHP current. This new method was validated by a simple theoretical model incorporating AHP and hyperpolarization-activated (Ih) currents and could be applied when the decay time constant of the AHP conductance was at least five times shorter than the estimatedIhactivation time. This condition was fulfilled in 33 of 44 motoneurons. The AHP conductance varied from 0.3 to 1.4 μS in both slow- and fast-type motoneurons, which was approximately the same range as the input conductance of the entire population. However, AHP and input conductances were not correlated. The larger AHP in slow-type motoneurons was mainly attributable to their smaller input conductance compared with fast motoneurons. The likeness of the AHP conductance in both types of motoneurons is in sharp contrast to differences in AHP decay time and explains why slow- and fast-type motoneurons have similar gain. |
| Databáze: | OpenAIRE |
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