Fig. 4: OMP-KO neurons are silenced by repetitive stimuli.

a Spontaneous firing rates of Het and KO neurons. Means: black bars. b Representative traces of firings induced by a single-odour stimulus in Het and KO neurons. Odourant mixtures contained amyl acetate, cineole, limonene, acetophenone, heptanal and lilial at a concentration of 100 μM each. c Representative traces of firings induced by repetitive odour stimuli in Het and KO neurons. d Time courses of the average firing rates of Het and KO ORNs shown in (c). Steady indicates the period between 5 and 10 s in (c). e Representative traces of spontaneous firings of Het and KO neurons under the loose patch-clamp configuration in the presence of db-cAMP and PDEi. The grey bars indicate the region with maximal frequency after perfusion. f Time courses of the average firing rates of ORNs shown in (e). The peak was determined at the position of the maximal frequency within a 5-s bin after perfusion of the test solution; other segments were determined within 10-s bins. Mean ± s.d. g Representative traces of spontaneous firing of Het and KO neurons during UV uncaging of membrane-permeable cAMP. h Time courses of the firing rates of the ORNs shown in (g). The initial rate was determined within a 5-s bin; other segments were determined within 10-s bins. Statistics: a two-sided unpaired T test; P = 0.548 (#), n = 70 and 47 ORNs from three Het and three KO mice, respectively. d Two-sided unpaired T test; the P-values for basal, steady and post are 0.4, 0.007 and 0.2. n = 5, each. f Two-sided unpaired T test; the P-values for basal max, i, ii and iii are 0.89, 0.84, 0.11, 0.028 and 0.000039, respectively; n = 5 ORNs each from three Het or three KO mice. h Two-sided T test; the P-values for basal, initial, steady and post are 0.18, 0.58, 0.0000022 and 0.95, respectively; n = 7 Het neurons and 8 KO neurons from three mice each. Mean ± s.d.