Figure 4: Electron micrograph of rat sciatic nerves. (a) Control group: myelinated fiber with normal structure and morphology. Axon is in normal condition too. (b) Sham group: Myelinated fiber shows myelin splitting (white arrow). Loosening of myelin lamellae may account for paler staining in the outer myelin sheath. Axonal degeneration was revealed with enlarged mitochondria (M) and neurofilament disintegration ((a) ×8900, (b) ×11500).