Inhibition of spontaneous network activity in neonatal hippocampal slices by energy substrates is not correlated with intracellular acidification.
J Neurochem
; 116(2): 316-21, 2011 Jan.
Article
en En
| MEDLINE
| ID: mdl-21083663
ABSTRACT
Several energy substrates complementary to glucose, including lactate, pyruvate and ß-hydroxybutyrate, serve as a fuel for neurons. It was reported recently that these substrates can substantially modulate cortical excitability in neonatal slices. However, complementary energy substrates (CES) can also induce an intracellular acidification when added exogenously. Therefore, action of CES on the neuronal properties governing excitability in neonatal brain slices may be underlain by a change in the cell energy status or by intracellular acidification, or both. Here, we attempt to elucidate these possibilities in neonatal hippocampus by recording neuronal population activity and monitoring intracellular pH. We show that a spontaneous network activity pattern, giant depolarizing potentials (GDPs), characteristic for the neonatal hippocampal slices exposed to artificial cerebrospinal fluid, is strongly inhibited by CES and this effect is unlikely to be caused by a subtle intracellular acidification induced by these compounds. Indeed, a much stronger intracellular acidification in the HCO(3) -free solution inhibited neither the GDP frequency nor the GDP amplitude. Therefore, modulation of neuronal energy homeostasis is the most likely factor underlying the effect of lactate, pyruvate and ß-hydroxybutyrate on network excitability in neonatal brain slices.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Metabolismo Energético
/
Hipocampo
/
Líquido Intracelular
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Red Nerviosa
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Inhibición Neural
Límite:
Animals
Idioma:
En
Revista:
J Neurochem
Año:
2011
Tipo del documento:
Article
País de afiliación:
Francia