Development of Action Potential Waveform in Hippocampal CA1 Pyramidal Neurons
| Autor: | A. Colino, Alberto Sanchez-Aguilera, M.A. Vicente-Torres, Gonzalo Monedero |
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| Přispěvatelé: | Ministerio de Ciencia, Innovación y Universidades (España) |
| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
Patch-Clamp Techniques Period (gene) Action Potentials Hippocampal formation Hippocampus 03 medical and health sciences 0302 clinical medicine Neurochemical Animals neuronal excitability development Subthreshold conduction Chemistry General Neuroscience Sodium channel Pyramidal Cells CA1 pyramidal neurons Depolarization Action potential potassium channels Potassium channel Rats Electrophysiology 030104 developmental biology Neuroscience 030217 neurology & neurosurgery sodium channels |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | CA1 pyramidal neurons undergo intense morphological and electrophysiological changes from the second to third postnatal weeks in rats throughout a critical period associated with the emergence of exploratory behavior. Using whole cell current-clamp recordings in vitro and neurochemical methods, we studied the development of the somatic action potential (AP) waveform and some of the underlying channels in this critical period. At the third postnatal week, APs showed a more hyperpolarized threshold, higher duration and amplitude. Subthreshold depolarization broadened APs and depolarized their peak overshoots more pronouncedly in immature neurons (2 weeks old). These features were mimicked by pharmacologically blocking the fast-inactivating A-type potassium current (I) and matched well with the higher concentrations of K4.2 and K4.3 and the lower concentrations of BK and K1.2 channels detected by Western blotting. Repetitive stimulation with high frequency trains (50 Hz) reproduced AP broadening associated to inactivation of the A-type current in immature cells. Moreover, repetitive firing showed changes in AP amplitude consistent with the inactivation of both sodium and potassium subthreshold currents, which resulted in higher AP amplitudes in the more immature neurons. We propose that maturation of AP waveform and excitability in this critical developmental period could be related to the onset of exploratory behaviors. This research was supported by DGICyT, grant numbers:SAF2007-61361 and SAF2010-20073. A S-A was supported with a Juan de la Cierva Formación Fellowship co-funded by the Spanish Ministry of Science, Innovation and Universities, and the CSIC. We thank Dr. Liset Menéndez de la Prida for her critical review of the manuscript. |
| Databáze: | OpenAIRE |
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