Extended Data Fig. 8: OT-R+ neurons outside of the preBötC do not discharge in phase with preBötC inspiratory bursts, the neurochemical phenotype of preBötCOT-R neurons is similar in P0 mice compared to adults, and characterization of the excitatory post-synaptic currents in nA neurons during inspiratory bursts.
a, All OT-R+ neurons recorded outside of the preBötC (Vm, whole-cell current-clamp recordings) showed activity patterns that were not in phase with the preBötC inspiratory-phase discharging population activity (n = 6 neurons, 3 tonic and 3 silent). b-c, In P0 triple transgenic mice, preBötCOT-R neurons show the same predominantly GABAergic (b) or glycinergic (c) phenotype as in adult mice (Extended Data Fig. 7e-g; arrows indicate OT-R and GAD67 or GlyT2 co-labelling). Scale bars: full images, 100 µm; insets, 50 µm. d, Same experiment as in Fig. 5k on a rhythmic preBötC slice from a neonatal wild-type mouse, here showing successive effects induced by the application of TGOT (0.5 µM), bicuculline (GABAA receptor antagonist, 10 µM), strychnine (glycine receptors antagonist, 5 µM), and CNQX (AMPA/kainate receptor antagonist, 20 µM), on preBötC population activity (⎰preBötC, integrated extracellular recordings) and on the currents recorded from a respiratory-modulated nA neuron that showed volleys of excitatory currents during inspiratory bursts following strychnine application (Im, whole-cell voltage-clamp recordings; Vh, -40 mV holding voltage). These excitatory currents were blocked by CNQX application, showing that they are induced by glutamatergic transmission (n = 3 mice).
