François A, Milliat F, Vozenin-Brotons MC, Mathe D, Griffiths NM. 'In-field' and 'out-of-field' functional impairment during subacute and chronic phases of experimental radiation enteropathy in the rat.
Int J Radiat Biol 2003;
79:437-50. [PMID:
12963546 DOI:
10.1080/0955300031000150594]
[Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE
To investigate subacute and chronic functional consequences of localized irradiation of rat small intestine on exposed and shielded segments (proximal and distal).
MATERIALS AND METHODS
The surgical model of a scrotal hernia was used. The ileal loop was exposed to single doses of 18, 21 or 29.6 Gy X-irradiation. Epithelial structure and transport capacity were followed 2 and 26 weeks post-exposure.
RESULTS
Irradiated segments showed mucosal ulceration followed by transmural fibrosis. Transport capacity was impaired from 2 to 26 weeks. Subacute functional impairment was noticed in the proximal segment, without either morphological alteration or neutrophil influx. At 26 weeks, both proximal and distal segments showed impaired epithelial transport capacity, with neutrophil influx in the submucosa in cases of 21-Gy exposure and in the submucosa and muscularis propria after 29.6 Gy.
CONCLUSIONS
Radiation enteritis was characterized by functional impairment, within as well as outside, the irradiation field. During the subacute phase, the irradiated segment may be a source of mediators which might influence intestinal function outside the site of injury via the blood stream and/or enteric nervous system. The development of an intestinal occlusion syndrome during the chronic phase might be responsible for intestinal dysfunction but it does not rule out a possible inflammatory process developing in the shielded parts of the small intestine.
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