Figure 7.

OMP alters spontaneous activity in an odorant-receptor-dependent manner. A–D, Baseline recordings in absence of stimulation from M71 OMP WTs (A) and OMP KOs (B) and mOR-EG OMP WTs (C) and OMP KOs (D). The red and dark blue traces represent low-pass filtered (50 Hz) recordings. The Ca²⁺-activated Cl⁻ channel blocker niflumic acid at 300 μm abolished basal activity. E, mOR-EG and M71 IBMX (1 mm, 1 s) responses were normalized to the responses of their respective ligand at 100 μm. The ratio is then plotted against the basal variance (averages of 8–24 ORNs). F, Average basal spike firing rate as a function of the basal variance (n = 8–10 ORNs). All data are expressed as mean ± SEM.