Radiation effects in the small bowel of the diabetic mouse

Purpose: Irradiation of the small intestine in the mouse induces damaging s tructural alterations to the architecture of the enteric mucosa. There is g rowing interest in the possible relevance of underlying additional patholog y when appreciating the total response of tissues to irradiation. The possi bility that small intestinal mucosal abnormalities in the streptozotocin-in duced diabetic mouse may exacerbate radiation-induced injury was tested by examining the combined effects of the two treatments. Material and methods: Streptozotocin-diabetic and -non-diabetic mice were e xposed to 10 Gy abdominal X-radiation. Profiles of mucosal epithelial cell populations were quantified and comparisons with corresponding groups of un irradiated mice made on the third day post-irradiation. Results: The histological appearances of the small intestinal mucosa were s imilar in both groups of irradiated mice, but the numbers of profiles of cr ypts and of columnar, goblet, Paneth and entero-endocrine cells were depres sed in these groups when compared with values in corresponding groups of un irradiated mice. However, the expression of radiation damage in the diabeti c mouse was less severe than in the non-diabetic mouse, particularly in the jejunum where the changes attendant on the onset of diabetes were most mar ked. Conclusion: These findings suggest that the response of mouse to radiation may be moderated by the presence of this type of pathophysiology. However, there is no evidence that the damage produced by streptozotocin-induced dia betes and radiation is additive.