Neuropathy of the peripheral and autonomic nervous system is known to be a common complication of diabetes mellitus. Although there are many studies investigating functional integrity of autonomic nerve of diabetic model by physiologic and
pharmacologic
approaches, morphological study of autonomic ganglion of diabetes mellitus is rare, In this study, we investigated changes in the fine structure of superior mesenteric ganglion of Vacor (N-3-pyridylmethyl-N'-pnitrophenylurea) induced diabetic
Mongolian
gerbil.
Oral dose of 10 ㎎ Vacor/㎏ of body weight/day was given for 30 days. Mean fasting blood glucose level in Vacor treated group (131.2±9.4㎎/dl, n=5) was significantly higher than that (66.8±8.1㎎/dl, n=5) of control group (p<0.01) . Degenerative
changes such as pyknotic nuclei, swelling of mitochondria, enlarged halo of secretory vesicles and vacuolar formation were observed in B cells of the pancreas of diabetic gerbil.
Some ganglion cells of superior mesenteric ganglion in diabetic gerbil showed an increase of lipofuscin granules, fusions of the granules and swelling of mitochondria. Satellite cells near the nerve fibers had well developed Golgi apparatus,
electron
dense bodies, lipid dropiets and multivesicular bodies in the cytoplasm. Near the blood vessels and degenerative nerve fibers, macrophages which had active phagocytic function were occasionally seem. Some nerve endings were swollen and contained
multilamellar bodies of membranous structures and their synaptic vesicels were decreased. Segmental demyelination and separation of myelin sheath were observed. The axoplasm of degenerative nerve fibers showed severe vacuolar changes and decrease
in
microtubules and microfilaments. Schwann cells near the myelinated nerve fibers had phyknotic nuclei, electron dense cytoplasm.
These results suggest that Vacor-induced diabetes mellitus induces degenerative changes of ganglion cells and nerve fibers of superior mesenteric ganglion of Mongolian gerbil.
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