TY - JOUR
T1 - Distinct alterations in colonic morphology and physiology in two rat models of enhanced stress-induced anxiety and depression-like behaviour
AU - O'Malley, Dervla
AU - Julio-Pieper, Marcela
AU - Gibney, Sinead M.
AU - Dinan, Timothy G.
AU - Cryan, John F.
N1 - Funding Information:
Declaration of interest. JFC and TGD are supported in part by Science Foundation Ireland in the form of a Centre grant (Alimentary Pharmabiotic Centre). The centre is also funded by GlaxoSmithKline.
PY - 2010/3
Y1 - 2010/3
N2 - Stress and anxiety are important causal and exacerbating factors in functional gastro-intestinal (GI) disorders such as irritable bowel syndrome. Stress affects GI motility, faecal transit and visceral pain sensitivity. Additionally, permeability and function of the gut epithelium, which acts as a barrier between the external environment and the body's internal milieu is altered by stress. However, the effects of an enhanced stress response on colonic morphology require further investigation. We have used two animal models of stress and anxiety, the maternally separated (MS) and Wistar Kyoto (WKY) rats to examine colonic morphology. These rats exhibit increased anxiety behaviours, visceral hypersensitivity and increased stress-induced defecation in the open field arena. At a morphological level, increased mucus secretion and an associated elevation in the number of mucosal goblet cells was observed in the high anxiety rats. Additionally, the mucosal layer was flattened in MS and WKY rats, a finding indicative of mild mucosal damage. Furthermore, the muscular layer of the distal colon in these animals was thickened, an observation that may have implications for faecal transit and visceral pain perception. This study provides evidence of altered colonic function and morphology in two animal models with a heightened response to stress.
AB - Stress and anxiety are important causal and exacerbating factors in functional gastro-intestinal (GI) disorders such as irritable bowel syndrome. Stress affects GI motility, faecal transit and visceral pain sensitivity. Additionally, permeability and function of the gut epithelium, which acts as a barrier between the external environment and the body's internal milieu is altered by stress. However, the effects of an enhanced stress response on colonic morphology require further investigation. We have used two animal models of stress and anxiety, the maternally separated (MS) and Wistar Kyoto (WKY) rats to examine colonic morphology. These rats exhibit increased anxiety behaviours, visceral hypersensitivity and increased stress-induced defecation in the open field arena. At a morphological level, increased mucus secretion and an associated elevation in the number of mucosal goblet cells was observed in the high anxiety rats. Additionally, the mucosal layer was flattened in MS and WKY rats, a finding indicative of mild mucosal damage. Furthermore, the muscular layer of the distal colon in these animals was thickened, an observation that may have implications for faecal transit and visceral pain perception. This study provides evidence of altered colonic function and morphology in two animal models with a heightened response to stress.
KW - Colonic morphology
KW - Irritable bowel syndrome
KW - Maternal separation
KW - Open field
KW - Stress
KW - Wistar Kyoto
UR - http://www.scopus.com/inward/record.url?scp=77649237408&partnerID=8YFLogxK
U2 - 10.3109/10253890903067418
DO - 10.3109/10253890903067418
M3 - Article
C2 - 20214436
AN - SCOPUS:77649237408
VL - 13
SP - 114
EP - 122
JO - Stress
JF - Stress
SN - 1025-3890
IS - 2
ER -