Fig. 1

Effect of vitamin D deficiency on lung function parameters in air- and CS-exposed mice after 6 and 12 weeks. At the age of 8 weeks, C57Bl/6J vitamin D deficient and control mice were exposed to CS or ambient air for a period of 6 or 12 weeks. Lung function was measured with whole-body plethysmography after 6 and 12 weeks of smoking. a The total lung capacity (TLC) and b lung compliance (Cchord). n = 10–12 per group per timepoint; mean ± SEM; *p < 0.05, **p < 0.01