Characterizing Enteric Neurons in Dopamine Transporter (DAT)-Cre Reporter Mice Reveals Dopaminergic Subtypes with Dual-Transmitter Content

This study characterizes dopaminergic neurons in the enteric nervous system (ENS) using a reporter mouse line expressing a fluorescent protein under the dopamine transporter (DAT) promoter. The research identifies distinct subtypes of dopaminergic neurons in the gut, some of which co-release acetylcholine and express canonical dopamine markers like TH, VMAT2, and GIRK2. A novel population of DA neurons, unique to the ENS, was discovered, characterized by the expression of Grp, Calcb, and Sst, and exhibiting a cholinergic phenotype. These findings highlight the heterogeneity of dopaminergic neurons in the gut and suggest further investigation into their functional roles and potential vulnerabilities in disease contexts.