Adult mice were unable to form supernumerary glomeruli in response to chronic odorant exposure.

<p>Figures A and B show representative I7tauGFP glomeruli from non-exposed mice and from those exposed to 10% heptaldehyde, respectively; periglomerular neuron autofluorescence (arrows) is commonly seen in adults. Scale bar 100 µm. The bar graph in C depicts the average number of I7 glomeruli per half bulb in mice exposed during early postnatal stage (PD0–PD20) and in those exposed during adulthood (PD50–PD70). Mann-Whitney U test: ***, P<0.001.