RESUMO
Context-induced retrieval of drug withdrawal memory is one of the important reasons for drug relapses. Previous studies have shown that different projection neurons in different brain regions or in the same brain region such as the basolateral amygdala (BLA) participate in context-induced retrieval of drug withdrawal memory. However, whether these different projection neurons participate in the retrieval of drug withdrawal memory with same or different molecular pathways remains a topic for research. The present results showed that (1) BLA neurons projecting to the prelimbic cortex (BLA-PrL) and BLA neurons projecting to the nucleus accumbens (BLA-NAc) participated in context-induced retrieval of morphine withdrawal memory; (2) there was an increase in the expression of Arc and pERK in BLA-NAc neurons, but not in BLA-PrL neurons during context-induced retrieval of morphine withdrawal memory; (3) pERK was the upstream molecule of Arc, whereas D1 receptor was the upstream molecule of pERK in BLA-NAc neurons during context-induced retrieval of morphine withdrawal memory; (4) D1 receptors also strengthened AMPA receptors, but not NMDA receptors, -mediated glutamatergic input to BLA-NAc neurons via pERK during context-induced retrieval of morphine withdrawal memory. These results suggest that different projection neurons of the BLA participate in the retrieval of morphine withdrawal memory with diverse molecular pathways.
Assuntos
Complexo Nuclear Basolateral da Amígdala , Morfina , Neurônios , Núcleo Accumbens , Síndrome de Abstinência a Substâncias , Animais , Complexo Nuclear Basolateral da Amígdala/metabolismo , Masculino , Síndrome de Abstinência a Substâncias/metabolismo , Síndrome de Abstinência a Substâncias/fisiopatologia , Morfina/farmacologia , Neurônios/metabolismo , Núcleo Accumbens/metabolismo , Memória/fisiologia , Receptores de AMPA/metabolismo , Ratos , Dependência de Morfina/metabolismo , Tonsila do Cerebelo/metabolismo , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Vias Neurais/metabolismo , Córtex Pré-Frontal/metabolismoRESUMO
The medial entorhinal cortex (MEC) is crucial for contextual memory, yet its role in context-induced retrieval of morphine withdrawal memory remains unclear. This study investigated the role of the MEC and its projection neurons from MEC layer 5 to the basolateral amygdala (BLA) (MEC-BLA neurons) in context-induced retrieval of morphine withdrawal memory. Results show that context activates the MEC in morphine withdrawal mice, and the inactivation of the MEC inhibits context-induced retrieval of morphine withdrawal memory. At neural circuits, context activates MEC-BLA neurons in morphine withdrawal mice, and the inactivation of MEC-BLA neurons inhibits context-induced retrieval of morphine withdrawal memory. But MEC-BLA neurons are not activated by conditioning of context and morphine withdrawal, and the inhibition of MEC-BLA neurons do not influence the coupling of context and morphine withdrawal memory. These results suggest that MEC-BLA neurons are critical for the retrieval, but not for the formation, of morphine withdrawal memory.