“…The composition of the rat sciatic nerve has been relatively well studied and morphometric parameters for myelinated fibers, such as fascicle area (Podhajsky and Myers, 1993;Di Benedetto et al, 1998), fiber count (Jenq and Coggeshall, 1985a,b;Jenq et al, 1986;Schmalbruch, 1986;Rodrıguez et al, 2000;Ceballos et al, 2002;Rafiuddin Ahmed and Jayakumar, 2003;Lago et al, 2005Lago et al, , 2007Prodanov and Feirabend, 2007), fiber density (number of myelinated fibers per fascicle unit area) (De Angelis et al, 1994;Rodrıguez et al, 2000;Mazzer et al, 2008), fiber packing (the percent of the fascicular area occupied by myelinated fibers) (Koller et al, 1992), mean fiber diameter (Le Beau et al, 1988;Koller et al, 1992;De Angelis et al, 1994;Di Benedetto et al, 1998;Prodanov and Feirabend, 2007), fiber diameter distributions (Strain and Olson, 1975;Schmalbruch, 1986;Wehling et al, 1992;Rodrıguez et al, 2000;Prodanov and Feirabend, 2007;Mazzer et al, 2008), and mean g-ratio (Adhami et al, 1976;De Angelis et al, 1994;Di Benedetto et al, 1998;Rodrıguez et al, 2000;Rafiuddin Ahmed and Jayakumar, 2003;Mazzer et al, 2008) or g-ratio distributions (Mazzer et al, 2008), have been described (Table 1). It is important to recognize that such data have been collected from multiple strains and from rats of varying ages, variables whose influence on morphometric parameters have not been exami...…”