Intestinal and colonic motor alterations associated with irradiation‐induced diarrhoea in rats

Abstract

Localized application of ionizing radiation to the gastrointestinal tract frequently elicits responses, which include diarrhoea. The origin of this symptom is not clear but has been attributed to loss of epithelial integrity, together with alterations in motility and increased secretion. The purpose of this study was to examine whether a 10 Gy abdominal gamma irradiation leads to an inflammatory reaction, and to compare intestinal and colonic motility in controls and abdominally irradiated rats 1, 3 and 7 days after irradiation, using an electromyographic technique. The motility parameters analysed were the frequency and velocity of propagation of migrating myoelectric complexes (MMC) in the jejunum and colonic spike activity (long spike bursts; LSB) per 10 min in fasted rats. The MMC frequency was significantly reduced on days 1 and 7 after irradiation and the MMC pattern was markedly disrupted on day 3. The frequency of colonic LSB was significantly reduced on days 1, 3 and 7. Mouth to anus transit was significantly accelerated on day 3 only and diarrhoea was observed at this time. Myeloperoxidase activity in the jejunum and colon was also increased on this day only. It is concluded that irradiation-induced diarrhoea occurs contemporaneously with disruption of MMC in the small intestine.

Plasma citrulline concentration: A surrogate end point for radiation-induced mucosal atrophy of the small bowel. A feasibility study in 23 patients

“…A wide diversity of functional disorders have been observed after ionizing radiation, such as motility dysfunction (1,2), changes in transepithelial transport processes (3,4), or the absorption of various nutrients, such as carbohydrates, amino acids, proteins, vitamins, and bile acid (5)(6)(7)(8)(9)(10). Acute radiation-induced smallbowel toxicity may necessitate treatment interruption, an established detrimental factor for treatment outcome (11).…”

Radiation enteropathy and leucocyte-endothelial cell reactions in a refined small bowel model

“…Topical radiation (abdominal and pelvic) [7-9] and more recently, segmental radiation of an isolated short segment of small intestine where different responses to radiation are examined [1,10]. We refined and developed the latter model, incorporating a platform where mice can be placed allowing exposure of the required segment of intestine for irradiation.…”

Differentially expressed proteins of gamma-ray irradiated mouse intestinal epithelial cells by two-dimensional electrophoresis and MALDI-TOF mass spectrometry

“…As genes encode proteins, we can deduce that proteins of intestinal epithelia can be induced by ionizing radiation [12] . These proteins are associated with many important cellular processes including DNA repair, apoptosis, cell cycle control, and oxidative stress response [13,14] . With accumulating evidences in the literature that new proteins are implicated in radiation response, the molecular mechanism underlying radiation response of the small intestine remains unknown.…”