Biologia, Bratislava 54/Suppl. 6: 239-245, 1999.
ISSN 0006-3088 (Biologia). ISSN 1335-6399 (Biologia. Section Cellular and Molecular Biology).
Changes in the myelin sheath of the peripheral nerve in experimental diabetes mellitus.
Eva Ochodnicka1*, Milan Ochodnicky2, Kamil Belej1, Elena Fusekova1 & Ludmila Boselova1
1 Institute of Histology and Embryology, Jessenius Faculty of Medicine, Comenius University, Mala Hora 4, SK-03601 Martin, Slovakia; tel.: ++ 421 842 315 31, e-mail: email@example.com.
2 Department of Internal Medicine 1, Jessenius Faculty of Medicine, Comenius University, Kollarova 2, SK-03659 Martin, Slovakia
* corresponding author
Received: January 12, 1999 / Accepted: October 5, 1999
The aim of the present study was to examine morphometric changes of myelin sheath of the peripheral nerve in the early stages of experimental streptozotocin diabetes mellitus. Adult male Wistar rats aged 17 wks were used in this study. Diabetes mellitus was induced by streptozotocin. Samples of the common peroneal nerve from diabetic rats (4 and 8 wks after induction of diabetes mellitus) and from age-matched control animals were removed and processed. The semi-thin cross sections were stained with toluidine blue and used for a computer-aided morphometric analysis of the myelinated fiber. No significant changes were found in diabetic animals after a 4 wk duration of the disease. There were significant reductions in the thickness of the myelin sheath and in the myelin sheath area in diabetic rats 8 wks after the induction of diabetes, in comparison with age-matched control animals. It can be concluded that the concomitant diminution of fiber area of the myelinated fibers of the peripheral nerve was caused predominantly by a reduction of the myelin sheath area because no significant reduction of the axonal area was observed in this group of diabetic rats. The present study demonstrates that the induction of diabetes mellitus in rat by streptozotocin is accompanied by early changes in the thickness of the myelin sheath and in the myelin sheath area indices of myelinated nerve fibers of the peripheral nerve.
Key words: myelin sheath, morphometry, peripheral nerve, diabetes mellitus, streptozotocin, rat.