iScience (Jul 2024)
Projection neurons from medial entorhinal cortex to basolateral amygdala are critical for the retrieval of morphine withdrawal memory
Abstract
Summary: 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.