Z Gastroenterol 2006; 44 - A83
DOI: 10.1055/s-2006-943449

Changes of the different neuropeptide containing nerve fibers and immunocells in diabetic rats' gastrointestinal tract

E Németh 1, B Batbayar 2, Á Vér 3, K Altdorfer 2, E Fehér 2
  • 1Department of Internal Medicine, Semmelweis University, Budapest, Hungary
  • 2Laboratory of Oral Morphology of the Faculty of Dentistry in the Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
  • 3Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary

Background and study aims: Peripheral neuropathy is a common complication of diabetes where neuropeptides and immunocells might play important roles in the pathogenesis of the disease. Materials and Methods: In this study we have quantified the different neuropeptide-containing nerve fibers, immunocells in streptozotocin-induced diabetic rat's gastrointestinal tract (pylorus, duodenum, and colon) using immunohisto-and cytochemical methods.

Results: The immunoreactive (IR) nerve fibers were found in all layers of the gastrointestinal tract and their distribution pattern was similar in both control and diabetic groups. Mast cell – nerve fiber contacts were rarely found in the controls. However, after four weeks duration of diabetes the number of IR nerve fibers and the immunocompetent cells was increased significantly (p<0.05) and the number of immunocytes – nerve fiber contacts was even more increased (p<0.001). The distance between nerve fibers and immunocells was m or even less. Some of the mast cells were degranulated in the µ about 1 vicinity of nerve fibers. No immunocompetent cells were observed having IR for any antisera in the control. However, after the streptozotocin-treatment, a large number of the immunocompetent cells showed immunoreactivity for substance P (SP) and neuropeptide Y (NPY). Counting all immunocompetent cells in whole sections showed that 12.3% of them were IR for SP and 25.4% was IR for NPY.

Conclusions: Increased number of SP-containing nerve fibers and immunocytes in diabetes mellitus might be the reason of painful neuropathy and might amplify the inflammatory reaction in an axon reflex manner; the released histamine and leukotriens, cytokines, chemokines might cause inflammation and lesions of the mucosa.