PVN-CRFR1 neurons make long-range projections to NTS. A, Schematic of the experimental design. B, A micrograph of the NTS from a CRFR1-Cre mouse injected with ChR2 into the PVN. Green, CRFR1-ChR2-YFP; blue, anti-tyrosine hydroxylase (TH) staining. C, Representative traces of laser-evoked EPSCs in a NTS neuron, which are blocked by AP5/DNQX and restored after washout. Gray lines, Individual traces; dark lines, averaged traces. D, Summary histogram of laser-evoked EPSCs in the NTS, which are blocked by AP5/DNQX (n = 6, p < 0.05, paired t test). E, Plot of the delay before an eEPSC from light onset in NTS neurons (n = 7). **p < 0.01.