Related Experiment Video
Updated: Jul 12, 2026
07:05
Important Endpoints and Proliferative Markers to Assess Small Intestinal Injury and Adaptation using a Mouse Model of Chemotherapy-Induced Mucositis
Published on: May 12, 2019
Radiation induced small bowel "web" formation is associated with acquired microvascular dysfunction.
O A Hatoum1, D G Binion, S A Phillips
1Division of Cardiovascular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA. ohatoum@mail.mcw.edu
Gut
|August 30, 2005
Summary
Radiation therapy can cause severe bowel issues like webs, leading to obstruction. This study found radiation-induced microvascular dysfunction in the small bowel contributes to these dangerous webs.
Area of Science:
- Gastroenterology
- Vascular Biology
- Oncology
Background:
- Radiation therapy for abdominal and pelvic cancers can cause severe late intestinal toxicity.
- This toxicity includes ischemia and stricture formation, presenting as
- webs
- potentially causing recurrent bowel obstruction.
Observation:
- A patient with anal cancer treated with radiation developed recurrent small bowel obstruction.
- Wireless capsule endoscopy revealed "webs" in the distal ileum, not visible on barium radiographs.
- Arterioles from the "web" and adjacent normal bowel were analyzed.
Findings:
- Microvessels from the radiation-induced "web" showed significantly reduced dilation to acetylcholine compared to normal bowel.
- Increased reactive oxygen species production was observed in microvessels from the "web".
- Histology revealed intimal and muscularis propria fibrosis narrowing the arterial lumen in the strictured bowel, with preserved endothelium.
Implications:
- External radiation therapy is linked to acquired microvascular endothelial dysfunction in the small bowel.
- This dysfunction plays a role in the pathogenesis of radiation-induced "web" formation.
- Understanding these mechanisms may lead to strategies for preventing or treating radiation-induced bowel injury.
Related Concept Videos
01:17Chronic Bowel Disorders: Introduction
Chronic bowel diseases are a group of long-term conditions affecting the digestive tract, characterized by inflammation and damage to the gut lining. These conditions primarily include irritable bowel syndrome and inflammatory bowel disease.
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
01:27Inflammatory Bowel Disease I: Ulcerative Colitis
Introduction
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
01:30Inflammatory Bowel Disease II: Crohn's Disease
Introduction
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by transmural...
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by transmural...
01:20Inflammatory Bowel Disease II: Ulcerative Colitis
Ulcerative colitis is a chronic inflammatory disorder of the colon characterized by continuous mucosal inflammation that typically begins in the rectum and extends proximally in a uniform pattern. Its pathogenesis involves a complex interplay of genetic predisposition, immune dysregulation, and environmental influences. These factors converge to impair the colon’s epithelial defenses and promote an exaggerated inflammatory response against luminal contents.Breakdown of the Mucosal BarrierA...
01:25Inflammatory Bowel Disease III: Crohn's Disease
Crohn’s disease is a chronic, relapsing form of inflammatory bowel disease characterized by segmental, transmural inflammation that can affect any part of the gastrointestinal tract. Its pathogenesis arises from a combination of genetic susceptibility, environmental exposures, epithelial barrier dysfunction, and immune dysregulation. Together, these factors lead to an exaggerated immune response against components of the gut microbiome.Genetic and Environmental InfluencesMultiple genetic...
01:20Inflammatory Bowel Disease IV: Clinical Manifestations
Inflammatory bowel disease (IBD) encompasses two major chronic disorders—ulcerative colitis and Crohn’s disease—each characterized by relapsing episodes of gastrointestinal inflammation. Although they share certain clinical features, their patterns of involvement and manifestations differ in ways that aid diagnosis and guide management.Ulcerative ColitisUlcerative colitis is limited to the colon and rectum and involves continuous inflammation of the mucosal layer. The disease course is marked...