Figure 1: Photomicrographs of toluidine-blue-stained semithin sections of rat sciatic nerve. (A, B) Control Group showing myelinated nerve fibers of various sizes with end oneurium (E) in between. (C–G) Aspartame Group showing (C) increased spaces (star) in between nerve fibers, (D–F) dilated blood vessel (arrow) containing many cells with irregular nuclei, (E) multiple myelin loops (arrow heads) and focal lysis of myelin sheath (biffed arrow) of some fibers, (F) excess demyelination and degeneration of myelin sheath (double arrow) in other fibers, and (G) irregular myelin thickening (waved arrow) in many nerve fibers. (H) Recovery Group showing nearly normal myelinated nerve fibers, Schwann cells (curved arrow) and endoneurium (E) in control group with some focal lysis (biffed arrow). Toluidine blue, 1000×.