Wnt7a in mouse insular cortex contributes to anxiety-like behavior during protracted abstinence from morphine.

•Morphine-dependent mice exhibit significantly anxiety-like behavior after protracted abstinence.•Activation of glutamatergic neuron and expression of Wnt7a in the medial IC are increased after protracted abstinence.•Lesion of the medial IC or down-regulation of Wnt7a in the medial IC alleviates the anxiety-like behavior.