Brief Reports
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 7, 2005; 11(5): 737-740
Published online Feb 7, 2005. doi: 10.3748/wjg.v11.i5.737
Effects of psychological stress on small intestinal motility and expression of cholecystokinin and vasoactive intestinal polypeptide in plasma and small intestine in mice
Shu-Guang Cao, Wan-Chun Wu, Zhen Han, Meng-Ya Wang
Shu-Guang Cao, Wan-Chun Wu, Zhen Han, Department of Gastroenterology, Yijishan Hospital, Wuhu 241001, Anhui Province, China
Meng-Ya Wang, Department of Physiology, Wannan Medical College, Wuhu 241001, Anhui Province, China
Author contributions: All authors contributed equally to the work.
Correspondence to: Wan-Chun Wu, Department of Gastroenterology, Yijishan Hospital, Wuhu 241001, Anhui Province, China. letous2002@163.com
Telephone: +86-553-5738401
Received: February 2, 2004
Revised: February 5, 2004
Accepted: February 26, 2004
Published online: February 7, 2005
Abstract

AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore the relationship between small intestinal motor disorders and gastrointestinal hormones under psychological stress.

METHODS: Thirty-six mice were randomly divided into psychological stress group and control group. A mouse model with psychological stress was established by housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. CCK and VIP levels in plasma and small intestine in mice were measured by radioimmunoassay (RIA).

RESULTS: Small intestinal transit was inhibited (52.18±19.15% vs 70.19±17.79%, P<0.01) in mice after psychological stress, compared to the controls. Small intestinal CCK levels in psychological stress mice were significantly lower than those in the control group (0.75±0.53 μg/g vs 1.98±1.17 μg/g, P<0.01), whereas plasma CCK concentrations were not different between the groups. VIP levels in small intestine were significantly higher in psychological stress mice than those in the control group (8.45±1.09 μg/g vs 7.03±2.36 μg/g, P<0.01), while there was no significant difference in plasma VIP levels between the two groups.

CONCLUSION: Psychological stress inhibits the small intestinal transit, probably by down-regulating CCK and up-regulating VIP expression in small intestine.

Keywords: Small intestine, Psychological stress, Cholecystokinin, Vasoactive intestinal polypeptide, Intestinal motility