Adiponectin increases the responsiveness of OSN populations which react to different odorous compounds.

<p>(<b>A</b>) Coronal section through ectoturbinate 2 of a mouse treated with buffer solution and exposed to 1-heptanal after <i>Egr-1</i> in situ-hybridisation. The boxed area is shown in B. (<b>B</b>) High magnification of the epithelium shows numerous <i>Egr1</i> positive cells. (<b>C</b>) High magnification of the same region as in B from a mouse treated with adiponectin and exposed to 1-heptanal. Numerous OSNs are E<i>gr-1</i> positive. (<b>D - E</b>) High magnification showing an area on ectoturbinate 2 from a buffer-treated mouse (D) and an adiponectin-treated mouse (E) after exposure to 2,3-hexanedione. (<b>F</b>) Number [n] of E<i>gr-1</i> positive cells on 50 consecutive sections through ectoturbinate 2 of control (white bars) and adiponectin-treated animals (black bars). Adiponectin increases the number of <i>Egr-1</i> positive cells for both odorants. (1-heptanal: control: 442.6±80.7; adipo+: 668.2±24.4; P = 0.0003; 2,3-hexanedione: control: 390.3±145.7; adipo+: 637.8±193.2; P = 0.0311). All numbers in this figure are given as means ± SD. ***, extremely significant; *, significant. Scale bar: 0,2 mm in A; 50 µm in B-E.