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Los péptidos opioides pueden excitar las neuronas piramidal del hipocampo al inhibir las interneuronas inhibidoras
Science (New York, N.Y.)
|July 27, 1979
Resumen
Los opiáceos excitan las células piramidal del hipocampo indirectamente al inhibir las interneuronas GABAérgicas. Este mecanismo puede explicar los efectos adictivos de las drogas y puede ser bloqueado por naloxona o bicuculina.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Neurofarmacología y Neurofarmacología.
- Electrofisiología Celular Electrofisiología celular
Sus antecedentes:
- Los opiáceos y los péptidos opioides exhiben una excitación atípica de las células piramidal del hipocampo.
- Comprender el mecanismo preciso de esta excitación es crucial para comprender la adicción a las drogas.
- Estudios anteriores sugirieron efectos directos, pero los mecanismos indirectos permanecieron sin explorar.
Objetivo del estudio:
- Para aclarar el mecanismo indirecto por el cual los opiáceos excitan las neuronas piramidal del hipocampo.
- Investigar el papel de las interneuronas inhibidoras en la mediación de los efectos de los opiáceos.
- Explorar la relevancia potencial de estos hallazgos para los signos electrográficos de la adicción a las drogas.
Principales métodos:
- Iontoforesis de naloxona, bicuculina y iones de magnesio para antagonizar la excitación.
- Estimulación transcallosa del hipocampo contralateral para evocar la inhibición recurrente.
- Registro electrofisiológico de las células piramidales del hipocampo.
Principales resultados:
- La excitación de las células piramidales inducida por opiáceos fue antagonizada por naloxona, bicuculina y iones de magnesio.
- La inhibición recurrente fue bloqueada por la encefalina y acortada por la acetilcolina.
- Los opioides parecen excitar las neuronas piramidal mediante la inhibición de las interneuronas cercanas que contienen ácido gamma-aminobutírico (GABA).
Conclusiones:
- La excitación inducida por opioides de las células piramidal del hipocampo es mediada indirectamente a través de la inhibición de las interneuronas GABAérgicas.
- Este mecanismo inhibidor indirecto es probablemente relevante para las manifestaciones electrográficas del uso de drogas adictivas.
- Dirigirse a esta vía inhibidora podría ofrecer nuevas estrategias terapéuticas para la adicción.
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