Histological and magnetic resonance analysis of sciatic nerves in the tellurium model of neuropathy.
Ingestion of tellurium (Te), a toxic element, produces paralysis of the hind limbs in weanling rats that is due to temporary, segmental demyelination of the sciatic nerves bilaterally. Weanling rats were fed a 1.1% elemental Te diet and sacrificed at various time points for histological and magnetic resonance (MR) analysis of the sciatic nerves. No controls exhibited impairments of the hind limbs, whereas Te-treated animals became progressively impaired with increased Te exposure. Toluidine blue-stained nerve sections of Te-treated animals showed widened endoneurial spaces, disrupted myelin sheaths, swollen Schwann cells, and a few instances of axonal degeneration. Te decreased healthy myelin by 68% and increased percent extracellular matrix by 45% on day 7. MR experiments showed a decrease in the area of the short T2 component, an increase in average T1, and an increase in the position of the intermediate T2 component in Te-treated nerves. The correlation coefficient for healthy myelin and average T1 was 0.88 and that for healthy myelin and the area underneath the short T2 component was 0.77. The area of the short T2 component has been postulated as the best measure of the process of demyelination.
Pun
Teresa W C
TW
Neuroscience Research and Division of Neurosurgery, Sunnybrook and Women's College Health Sciences Center, Toronto, ON, Canada.
Odrobina
Ewa
E
Xu
Qing-Gui
QG
Lam
Toby Y J
TY
Munro
Catherine A
CA
Midha
Rajiv
R
Stanisz
Greg J
GJ
D000818:Animals; D003711:Demyelinating Diseases / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000473:pathology; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging; D010523:Peripheral Nervous System Diseases / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000473:pathology*; D011859:Radiography; D051381:Rats; D011917:Rats, Inbred Lew; D012584:Sciatic Nerve / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D013691:Tellurium / Q000633:toxicity*
D013691:Tellurium