Efferent-mediated activation of excitatory nAChRs on CD afferents does not require α9α10 nAChRs. A, B, Average response histogram of a BM and CD afferent to the standard efferent shock train before and during application of 1 μm MLA, respectively. C, Average response histogram of a BT afferent to the standard efferent shock train before and during application of 1 μm αBTX. D, Average response histogram of a CD afferent to the standard efferent shock train before and during the serial application of 3 μm αBTX and 20 μm DMPP. E, Average response histogram of a BM afferent to the standard efferent shock train before and during application of 333 nm α-CtxRgIA. F, Average response histogram of a CD afferent to the standard efferent shock train before and during serial application of 667 nm α-CtxRgIA and 5 μm DMPP. Efferent shock trains (20 shocks at 200/s, black bar at t = 0) were repeated every 3 s and all histograms were based on ≥19 shock train presentations.