Extended Data Fig. 4: Oxtr rather than Glp1r VANs are the major vagal input to PPG^NTS neurons.

a, Photomicrograph of coronal NTS section from PPG-Cre:tdRFP mouse transduced with DIO-TVA-mCherry + DIO-RabiesG, and subsequently with rabies virus-ΔG-GFP (RABV). Bilateral NTS injection of TVA + RabiesG and counterbalanced unilateral injection of RABV (4 mice / side) resulted in 40.5% (±5.5) of all PPG^NTS neurons being successfully transduced ‘starter’ neurons, identified by colocalisation of mCherry (and/or tdRFP) and GFP (photomicrographs in a-h representative of independent experiments from 8 animals). Despite unilateral RABV injection, starter neurons were observed in left and right NTS in all mice, indicating substantial viral spread and bilateral transduction. Scale=100μm. b, Total RABV + cells in left and right nodose ganglia (LNG / RNG; n = 6 / 7 biologically independent samples), unpaired 2-tailed t-test: t(11)=0.214, p = 0.834. c,d, Quantification of Glp1r and Oxtr colocalisation in nodose ganglia (c), and proportions of dual-expressing Glp1r / Oxtr cells colocalised with RABV (d). This dual population comprises 24.7% of all Glp1r cells and 19.7% of all Oxtr cells. 9% of RABV + vagal inputs to PPG^NTS neurons express both Glp1r and Oxtr, and 26.1% of dual-expressing Glp1r / Oxtr cells are RABV + vagal inputs to PPG^NTS neurons. e, Quantification of RABV and Glp1r colocalisation in NG as proportions of all RABV + cells and all Glp1r+ cells, including those Glp1r cells that also express Oxtr. f, Quantification of RABV and Oxtr colocalisation in NG as proportions of all RABV + cells and all Oxtr+ cells, including those Oxtr cells that also express Glp1r. g,h, Photomicrographs of left and right nodose ganglion sections showing rabies virus GFP expression (RABV) and Glp1r and Oxtr FISH. RABV + Glp1r colocalisation shown by white arrows, RABV + Oxtr by green arrows and RABV + Glp1r+Oxtr by white-edged green arrow. Scale=100μm. All data presented as mean ± SEM.