[Somatostatin interneurons of prelimbic cortex in regulating morphine-induced behavior changes].

Drug addiction is a chronic psychiatric disorder characterized by compulsive drug taking, and involves neuronal plasticity changes in multiple brain regions. The prelimbic cortex (PrL) is a key region of the dorsomedial prefrontal cortex and contains majority of pyramidal neurons. The excitatory projections from PrL play a very important role in the drug seeking behaviors. PrL also contains a small amount of GABAergic interneurons, which regulate the information integration and transmission of the pyramidal neurons. However, the roles of the GABAergic interneurons in PrL in drug-induced behavior changes are not clear. In the PrL, parvalbumin (PV) and somatostatin (SST) interneurons are two major GABAergic interneurons, which have been reported to regulate the activity of glutamatergic input, and form inhibitory synaptic transmission to regulate the output of downstream signals. Here, we used PV-Cre and SST-Cre mice combined with chemical genetics to explore the role of PV and SST interneurons in PrL in morphine-induced behavior changes. Our data showed that specific inhibiting SST interneurons in PrL significantly increased the anxiety level and decreased morphine-induced locomotor activity and the conditioned place preference (CPP) score. Instead, specific inhibiting PV interneurons in PrL had no effect on the anxiety level, morphine induced-locomotor activity and CPP. Our findings provide a new insight into the cellular and neuronal specific mechanism for drug addiction.