Research Paper Volume 9, Issue 3 pp 880—899

Functional decline at the aging neuromuscular junction is associated with altered laminin-α4 expression

Figure 3. Weaker hind-limb grip force but normal distribution of different fiber types in lama4-/-. (A) Body weight of animals and (B) normalized grip force over body weight. Aged WT dropped in grip force/body weight tremendously and reached the similar level of motor performance to that of lama4-/-. (C) Triple labelling staining for different fiber types at 3MO and aged group; blue staining represents Type I, green represents Type IIA, red represents Type IIB and unstained fibers represents Type IIX in gastrocnemius muscle. Scale bar = 100 μm. (D, E) Distribution of each different fiber types at both ages of 3MO and aged was normal in both genotypes. (A-B), n = 8 for each genotype per age group investigated. (D-E), n = 5 for each genotype, with >1000 fibers counted for each genotype at 3MO and aged groups. Statistical analyses were performed using Student’s t-test; values are presented as mean ± SEM (*** P < 0.001 and **** P < 0.0001).