Three-dimensional study of the capillary supply of skeletal muscle fibres using confocal microscopy

Three-dimensional (3D) study of capillary network of individual muscle fibr es in rat extensor digitorum longus (EDL) and soleus (SOL) muscles is prese nted. Stereology and 3D reconstruction techniques were applied to stacks of serial optical sections recorded by a confocal microscope from thick muscl e slices. The results suggest that SOL muscle fibres have a larger surface area and volume as well as a larger length of capillaries per fibre length than EDL. On the other hand, these two muscles have a similar ratio of capi llary length to fibre surface area. The 3D approach to evaluation of muscle fibre capillarization brings many advantages over traditional measurements made on single muscle sections and could also be applied to the study of a ngiogenesis in other tissues.