Fig. 7.

Composition of alveolar septal walls. Stereological data; mean and individual data of n = 4 (Sftpd^−/−) and n = 5 (WT and DiNOS) are shown. The absolute volumes of the blood-gas barrier [V(bgb,sep)], capillary lumen [V(cap,sep)], alveolar epithelium [V(alvepi, sep)], interstitial tissue [V(inter, sep)], interstitial cells [V(IC, sep)], and extracellular matrix [V(ECM, sep)] are presented. The volume of the blood-gas barrier is increased in Sftpd^−/− but not in DiNOS mice, whereas virtually no differences in capillary volume can be seen. Increase in the volume of the blood-gas barrier can be attributed to alveolar epithelium and interstitial tissue. One-way ANOVA on ranks followed by Bonferroni correction was performed for statistical analyses.