Cell-Type Specific Induction of Cyclo-Oxygenase-2 in Layer II/III Prefrontal Cortical Neurons Mediates StressInduced Anxiety Phenotypes in Mice

The ability of the medial prefrontal cortex (mPFC) to exert top-down control of behavior is affected by stress. The molecular response of mPFC to stress is incompletely understood, however, in part because of the region’s cellular heterogeneity. Here we used single nucleus RNA sequencing (snRNAseq) to map specific molecular cell types within the mPFC and to detect cell-type specific transcriptional changes to foot-shock stress. We identified Ptgs2 , encoding cyclo-oxygenase 2, as an important candidate that is upregulated in layer II/III excitatory neurons after stress. Specifically, Ptgs2 was transiently upregulated with shock-induced fear learning and fear expression, along with Bdnf, Nptx2 , and Lingo1 , in a layer II/III neuronal population marked by the neuronal excitatory gene Slc17a7 and cell-type specific neuropeptide Penk . These dynamic cell-type specific expression patterns identified with snRNAseq were validated with quantitative fluorescent in situ hybridization. Using a pharmacological approach, we found that systemic lumiracoxib, a selective Ptgs2-inhibitor, led to a significant reduction in fear expression. Furthermore, genetic ablation of Ptgs2 in excitatory Camk2a -expressing neurons led to reduced stress-induced anxiety-like behaviors. Together these findings suggest that Ptgs2 is expressed in a dynamic, cell-type specific way in Layer II/III Penk + neurons in mPFC, and that its role in prostaglandin and /or endocannabinoid regulation within these neurons may be an important mediator of stress-related behavior. ### Competing Interest Statement The authors have declared no competing interest.