ACRYLAMIDE-INDUCED NEUROPATHIC CHANGES IN RAT ENTERIC NERVES - SIMILARITIES WITH EFFECTS OF STREPTOZOTOCIN-DIABETES

The effect of acrylamide intoxication (a widely used model for autonom ic neuropathy) on the fluorescence intensity and density of catecholam ine- and peptide-containing nerve fibres and tissue content of noradre naline and the peptides vasoactive intestinal polypeptide, calcitonin gene-related peptide, substance P and neuropeptide Y in the enteric ne rves of rat ileum was examined. Histochemical and immunohistochemical techniques were used to localize catecholamine- and peptide-containing nerve fibres. The tissue content of nondrenaline was measured using h igh-performance liquid chromatography, and an enzyme-linked immunosorb ent assay technique was used To determine the tissue content of the pe ptides investigated. Acrylamide intoxication caused a significant decr ease in the density of catecholamine-containing nerve fibres and tissu e content of noradrenaline in the myenteric plexus of rat ileum. A dec rease in tissue content and immunoreactivity of calcitonin gene-relate d peptide and an increase in vasoactive intestinal polypeptide was see n in the myenteric plexus of ileum from acrylamide-intoxicated rats. I n the submucous plexus, the acrylamide treatment caused a decrease in calcitonin gene-related peptide immunoreactivity and an increase in va soactive intestinal polypeptide and neuropeptide Y immunoreactivity. T here was no change in either tissue content or immunoreactivity of sub stance P in both myenteric and submucous plexuses of the treated rat i leum. These changes have a striking similarity with those found in the enteric nerves of streptozotocin-diabetic rat ileum, suggesting the p ossible presence of an underlying common mechanism(s) in the developme nt of neuropathic changes in the autonomic nerves of acrylamide-intoxi cated and streptozotocin-diabetic rats.