Figure 3

Distribution of Crh , Crhbp , Crhr2b , Mc2r , and Nr3c1 mRNAs in mouse fetal lungs. Mouse tissue sections are from GD 15.5 (A, C, E, G and I) or 17.5 (B, D, F, H and J). In situ hybridization was performed using anti-sense probes (A to J, positive signal is blue). No staining was observed using corresponding sense probes (negative controls, data not shown). Results obtained on GD 16.5 (data not shown) are similar to those obtained on GD 15.5 for all the genes. A change in expression sites between GD 15.5-16.5 versus 17.5 was observed. Expression of mRNAs encoding for all the analyzed genes was observed in epithelial cells of distal zones on GD 17.5. Scale bars, 50 μm (A to J). CZ, conducting zone; E, epithelial cells; EC, endothelial cell; M, mesenchyme; RZ, respiratory zone; SM, smooth muscle.