Fig. 1.

Expression of marker proteins in the VNO of cGαi2^+/− and cGαi2^−/− mice. (A) Loss of Gαi2 immunoreactivity in cGαi2^−/− VNO. Antibodies specific for PDE4A (apical layer) or V2R2 (basal layer) indicate that the laminar VNO organization persists in the absence of Gαi2. (Scale bars, 50 μm.) (B) Relative expression (normalized to Hprt-1) of Gnai2, Gnao, and Omp genes in VNO (Left) and MOE (Right). Gnai2 expression decreased and Gnao expression increased, whereas Omp expression did not change, in cGαi2^−/− VNO [**P < 0.01 and ***P < 0.001; nonsignificant (NS), P = 0.21, Mann–Whitney U test; cGαi2^+/−, n = 20; cGαi2^−/−, n = 18]. No difference in gene expression in the MOE between the two genotypes was observed (NS, P = 0.22–0.53, Mann–Whitney U test). (C) Analysis of apical and basal VNO layer volume distinguished by PDE4A immunostaining indicates a significant reduction in the apical VNO layer [t test, t(46) = 3.975; ***P < 0.001] and an increase in basal VNO layer [t test, t(46) = 3.929; ***P < 0.001] of cGαi2^−/− (n = 27) vs. cGαi2^+/− mice (n = 21). L, lumen; LP, lamina propria. Data are expressed as means ± SEM. (Scale bars, 50 µm.)