Monosynaptic inputs to dopamine neurons in the ventral tegmental area and substantia nigra compacta and serotonin neurons in the dorsal raphe and median raphe

Monosynaptic inputs to serotonin neurons in the dorsal raphe (DR) and median raphe (MnR) were labeled in mice using the modified rabies virus SADdG-GFP (envA). The anatomical location and corresponding brain regions of labeled input neurons were systematically recorded and stored using MATLAB. This dataset includes the extracted input mapping data, along with the custom MATLAB codes used for data extraction, processing, and analysis of the retrograde tracing experiments.

Methods
Virus for Cre-dependent expression of receptor (AAV5-FLEX-TVA-mCherry) and rabies G protein (AAV8-FLEX-RG) were injected into the dorsal raphe (DR) or median raphe (MnR) of serotonin transporter (Sert)-Cre mice. 2 weeks later, pseudotyped modified rabies virus (SADdG-GFP(envA)) was injected at the same location. The brain was fixed with phosphate-buffered saline (PBS) and paraformaldehyde (PFA) serial perfusion, and cut into 100 μm coronal sections. Every 3 sections of the obtained brain sections were counter-stained with NeuroTrace Fluorescent Nissl Stains (Molecular Probes) and imaged with Zeiss AxioImager Z2 using a 10x lens. GFP-labeled neurons were manually registered onto brain areas based on Paxinos and Franklin’s atlas.