Neonatal general anesthesia causes lasting alterations in excitatory and inhibitory synaptic transmission in the ventrobasal thalamus of adolescent female rats.
Neurobiol Dis
; 127: 472-481, 2019 07.
Article
en En
| MEDLINE
| ID: mdl-30825640
ABSTRACT
Ample evidence has surfaced documenting the neurotoxic effects of various general anesthetic (GA) agents in the mammalian brain when administered at critical periods of synaptogenesis. However, little is known about how this neurotoxic insult affects persisting neuronal excitability after the initial exposure. Here we investigated synaptic activity and intrinsic excitability of the ventrobasal nucleus (VB) of the thalamus caused by neonatal GA administration. We used patch-clamp recordings from acute thalamic slices in young rats up to two weeks after neurotoxic GA exposure of isoflurane and nitrous oxide for 6â¯h at postnatal age of 7 (P7) days. We found that GA exposure at P7 increases evoked excitatory postsynaptic currents (eEPSCs) two fold by means through AMPA mediated mechanisms, while NMDA component was spared. In addition, miniature EPSCs showed a faster decay rate in neurons from GA treated animals when compared to sham controls. Likewise, we discovered that the amplitudes of evoked inhibitory postsynaptic currents (eIPSCs) were increased in VB neurons from GA animals about two-fold. Interestingly, these results were observed in female but not male rats. In contrast, intrinsic excitability and properties of T-type voltage gated calcium currents were minimally affected by GA exposure. Together, these data further the idea that GAs cause lasting alterations in synaptic transmission and neuronal excitability depending upon the placing and connectivity of neurons in the thalamus. Given that function of thalamocortical circuits critically depends on the delicate balance between excitation and inhibition, future development of therapies aimed at addressing consequences of altered excitability in the developing brain by GAs may be an attractive possibility.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Transmisión Sináptica
/
Anestésicos por Inhalación
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Núcleos Talámicos Ventrales
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Isoflurano
/
Neuronas
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Óxido Nitroso
Tipo de estudio:
Etiology_studies
Límite:
Animals
Idioma:
En
Revista:
Neurobiol Dis
Asunto de la revista:
NEUROLOGIA
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
EEUU
/
ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
/
USA