Schwann cells associated with vestibular ganglion cells in the aging rat.
The purpose of this study was to quantify any age-related change in the components of Schwann cells associated with vestibular ganglion cells: adperikaryonal Schwann cell cytoplasm, myelin bubbles, compact myelin, Schwann cell lipofuscin, or mitochondria in addition to extracellular intraganglionic space. Studies were carried out in young (Y, 3 to 5 months of age, N = 6), old (0, 24 to 26 months of age, N = 3), and very old (VO, 28 to 31 months of age, N = 6) female Wistar rats using point counting stereologic techniques. Recent reports have demonstrated age-related increases in the peripheral nerve counterparts to the following entities: adaxonal Schwann cell cytoplasm, myelin bubble, endoneurial space, and a decrease in Schwann cell mitochondria. Our results indicate no age-related change in the volume fraction of extracellular intraganglionic space (Y, 0.179 +/- 0.04; O, 0.174 +/- 0.049; VO, 0.205 +/- 0.043), adperikaryonal Schwann cell cytoplasm (Y, 0.026 +/- 0.008; O, 0.019 +/- 0.003; VO; 0.028 +/- 0.007), myelin bubble (Y, 0.004 +/- 0.003; O, 0.011 +/- 0.009; VO, 0.006 +/- 0.002), Schwann cell lipofuscin (Y, 0.002 +/- 0.001; O, 0.004 +/- 0.003; VO, 0.002 +/- 0.001), or mitochondria (Y, 0.194 +/- 0.019; O, 0.208 +/- 0.024; VO, 0.205 +/- 0.04). The only age-related change was an increase in compact myelin (Y, 0.006 +/- 0.001; O, 0.008 +/- 0.006; VO, 0.011 +/- 0.004). These findings differ from those of the peripheral nerve.(ABSTRACT TRUNCATED AT 250 WORDS)
Carney
M E
ME
Department of Otolaryngology and Communication Sciences, SUNY Health Science Center, Syracuse 13210.
Lyon
M J
MJ
D000375:Aging / Q000473:pathology*; D000818:Animals; D005260:Female; D008854:Microscopy, Electron; D009186:Myelin Sheath / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D012583:Schwann Cells / Q000648:ultrastructure*; D014725:Vestibular Nerve / Q000648:ultrastructure*