Quantitative analysis of myelinated nerve fibers of peripheral nerve in streptozotocin-induced diabetes mellitus

Abstract

The purpose of this study was to examine morphometric changes of myelinated fibers in early stages of experimental diabetes mellitus. Adult male Wistar rats aged 17 wk were used in this study. Diabetes mellitus was induced by streptozotocin. Samples of common peroneal nerve from diabetic rats (4 and 8 wk after induction of diabetes mellitus) and age-matched control animals were removed and processed. The semithin cross sections were stained with toluidine blue and used for myelinated fiber computer-aided morphometric analysis. There were no significant changes in diabetic animals after 4 wk duration of the disease. There was significant reduction in myelinated nerve fiber caliber in diabetic rats 8 wk after induction of diabetes as compared to age-matched controls. There was no significant reduction of axonal area in this group of diabetic rats, so diminution of fiber area was caused predominantly by reduction of myelin sheath area. The study demonstrates that the induction of diabetes mellitus in rat by streptozotocin is accompanied by early changes of the morphometric indices of myelinated nerve fibers of peripheral nerve.

The effect of spinal cord stimulation frequency in experimental painful diabetic polyneuropathy

“…In PDP small sensory fibres, including unmyelinated C‐fibres and thinly myelinated Aδ‐fibres are primarily targeted early in the disease process (Loseth et al., ), whereas large myelinated sensory fibres are only affected later in the disease process (Said et al., ). In STZ‐induced diabetic rats, morphometric changes to myelinated nerve fibres have been reported 4–8 weeks after induction of DM (Ochodnicka et al., ). In our study, SCS was applied 4 weeks after induction of DM, when painful symptoms have clearly developed.…”

Reduction in voltage‐gated K+ channel activity in primary sensory neurons in painful diabetic neuropathy: role of brain‐derived neurotrophic factor

“…2002). In addition, damage to large myelinated afferent fibers is well known in diabetic neuropathy (Ochodnicka et al. 1995).…”

Neurotrophic modulation of myelinated cutaneous innervation and mechanical sensory loss in diabetic mice

“…However, the vast majority of studies addressing axon loss in diabetes have focused on C-fiber loss in the epidermis and information regarding dermal innervation by myelinated fibers has been largely ignored (see . This is surprising since ultrastructural damage to myelinated fibers in diabetic neuropathy has been reported in both animals and patients (Yagihashi et al, 1990;Ochodnicka et al, 1995;Weis et al, 1995;. Electrophysiological studies in diabetic rats suggest that the increased sensory input from myelinated afferents plays an important role in diabetic neuropathic pain (Khan et al, 2002).…”