Fig. 3From: Age-related morphological regression of myelinated fibers and capillary architecture of distal peripheral nerves in ratsCross-sectional images of the tibial nerve stained with 1 % toluidine blue. The black arrows indicate myelinated fibers. Each densely stained outer ring indicates a myelin sheath. The myelin sheaths and axons of the myelinated fibers in a young rat appear to be thicker and larger than those of an elderly rat (a a young rat, b an elderly rat). Scale bar 10 μmBack to article page