Diaphragm Muscle Weakness Following Acute Sustained Hypoxic Stress in the Mouse Is Prevented by Pretreatment with N-Acetyl Cysteine

Figure 11

Mouse diaphragm muscle fibre size and distribution following exposure to 8 hours of normoxia (control) or hypoxia. (a) Representative images of mouse diaphragm muscle immunofluorescently labelled for laminin to highlight individual fibres from animals exposed to 8 hours of normoxia (control, FiO₂ = 0.21) and hypoxia (FiO₂ = 0.10). (b) Group data for mean minimal Feret’s diameter. (c) Group data for mean muscle fibre cross-sectional area. (d) Group data for coefficient of variation of diaphragm muscle fibre size measured by minimal Feret’s diameter. (e) Group data for coefficient of variation of diaphragm muscle fibre size measured by cross-sectional area. Data in (b–e) expressed as mean ± SEM; there were no significant differences between groups ( per group; unpaired Student’s t-tests). (f) and (g) Relative frequency distribution of diaphragm muscle fibres measured by minimal Feret’s diameter (f) and cross-sectional area (g).

(a)

(b)

(c)

(d)

(e)

(f)

(g)