The adherent gastrointestinal mucus gel layer: thickness and physical state in vivo.

Divergent results from in vitro studies on the thickness and appearance of the gastrointestinal mucus layer have previously been reported. With an in vivo model, we studied mucus gel thickness over time from stomach to colon. The gastrointestinal tissues of Inactin-anesthetized rats were mounted luminal side up for intravital microscopy. Mucus thickness was measured with a micropipette before and after mucus removal by suction. The mucus layer was translucent and continuous; it was thickest in the colon (approximately 830 microm) and thinnest in the jejunum (approximately 123 microm). On mucus removal, a continuous, firmly adherent mucus layer remained attached to the epithelial surface in the corpus (approximately 80 microm), antrum (approximately 154 microm), and colon (approximately 116 microm). In the small intestine, this layer was very thin (approximately 20 microm) or absent. After mucus removal, there was a continuous increase in mucus thickness with the highest rate in the colon and the lowest rate in the stomach. In conclusion, the adherent gastrointestinal mucus gel in vivo is continuous and can be divided into two layers: a loosely adherent layer removable by suction and a layer firmly attached to the mucosa.

[1]  K. Matsuo,et al.  Histochemistry of the surface mucous gel layer of the human colon. , 1997, Gut.

[2]  A. M. Roberton,et al.  Mucin degradation and its significance in inflammatory conditions of the gastrointestinal tract , 1999 .

[3]  G. Macfarlane,et al.  Contribution of the microflora to proteolysis in the human large intestine. , 1988, The Journal of applied bacteriology.

[4]  C. Cross,et al.  ANTIOXIDANT PROTECTION: A FUNCTION OF TRACHEOBRONCHIAL AND GASTROINTESTINAL MUCUS , 1984, The Lancet.

[5]  J. Pearson,et al.  Is the colonic mucus barrier multilayered , 1999 .

[6]  J. Costerton,et al.  Microbial flora of the mouse ileum mucous layer and epithelial surface , 1982, Applied and environmental microbiology.

[7]  R. Newcombe,et al.  Thickness of adherent mucus gel on colonic mucosa in humans and its relevance to colitis. , 1994, Gut.

[8]  E. Kivilaakso,et al.  Demonstration of a pH gradient at the luminal surface of rat duodenum in vivo and its dependence on mucosal alkaline secretion. , 1983, Gastroenterology.

[9]  E. Nilsson,et al.  Mucus and alkali secretion in the rat duodenum: effects of indomethacin, N omega-nitro-L-arginine, and luminal acid. , 1995, Gastroenterology.

[10]  L. Holm,et al.  Microscopy of acid transport at the gastric surface in vivo , 1990, Journal of internal medicine. Supplement.

[11]  C. Venables,et al.  Changes in the structure of the mucous gel on the mucosal surface of the stomach in association with peptic ulcer disease. , 1982, Gastroenterology.

[12]  J. Kaunitz,et al.  Dynamic regulation of gastric surface pH by luminal pH. , 1999, The Journal of clinical investigation.

[13]  A. Persson,et al.  Stimulation of acid secretion increases the gastric gland luminal pressure in the rat. , 1992, Gastroenterology.

[14]  J. Dekker,et al.  Biosynthesis of human colonic mucin: Muc2 is the prominent secretory mucin. , 1994, Gastroenterology.

[15]  The colonic mucus barrier and changes in inflammatory bowel disease , 1998 .

[16]  J. Kaunitz,et al.  Dynamic regulation of mucus gel thickness in rat duodenum. , 2000, American journal of physiology. Gastrointestinal and liver physiology.

[17]  K. J. Obrink,et al.  Rat gastric mucosal microcirculation in vivo. , 1985, The American journal of physiology.

[18]  A. Paerregaard.  [Gastrointestinal mucus]. , 1996, Ugeskrift for laeger.

[19]  J. Chayvialle,et al.  Effects of neurotransmitters, gut hormones, and inflammatory mediators on mucus discharge in rat colon. , 1998, American journal of physiology. Gastrointestinal and liver physiology.

[20]  T. Kawakami,et al.  Distinct effects of tetragastrin, histamine, and CCh on rat gastric mucin synthesis and contribution of NO. , 1998, American journal of physiology. Gastrointestinal and liver physiology.

[21]  S. Halm,et al.  Secretagogue response of goblet cells and columnar cells in human colonic crypts 1 , 1999 .

[22]  F. Plum.  Handbook of Physiology. , 1960 .

[23]  I. Khatri,et al.  Susceptibility of the cysteine-rich N-terminal and C-terminal ends of rat intestinal mucin muc 2 to proteolytic cleavage. , 1998, The Biochemical journal.

[24]  J. Huntley,et al.  Immune exclusion and mucus trapping during the rapid expulsion of Nippostrongylus brasiliensis from primed rats. , 1981, Immunology.

[25]  S. Kerss,et al.  A simple method for measuring thickness of the mucus gel layer adherent to rat, frog and human gastric mucosa: influence of feeding, prostaglandin, N-acetylcysteine and other agents. , 1982, Clinical science.

[26]  J. F. Brown,et al.  Nitric oxide generators and cGMP stimulate mucus secretion by rat gastric mucosal cells. , 1993, The American journal of physiology.

[27]  J. Pearson,et al.  The gastrointestinal adherent mucous gel barrier. , 2000, Methods in molecular biology.

[28]  K. Miyakawa,et al.  Measurement of leukotriene B4 in arterial blood of asthmatic patients during wheezing attacks , 1990, Journal of internal medicine.

[29]  L. Engstrand,et al.  Adherent surface mucus gel restricts diffusion of macromolecules in rat duodenum in vivo. , 1999, The American journal of physiology.

[30]  G. Niehans,et al.  Expression cloning of gastric mucin complementary DNA and localization of mucin gene expression. , 1995, Gastroenterology.

[31]  G. Forstner.  Signal transduction, packaging and secretion of mucins. , 1995, Annual review of physiology.

[32]  J. Newton,et al.  A novel method for the visualization of the in situ mucus layer in rat and man. , 1998, Clinical science.

[33]  L. Holm,et al.  Hydrogen ion concentration in the mucus layer on top of acid-stimulated and -inhibited rat gastric mucosa. , 1994, Gastroenterology.

[34]  太田 浩良.  Alternating laminated array of two types of mucin in the human gastric surface mucous layer , 1992 .

[35]  J. Pearson,et al.  Patients with ulcerative colitis have reduced mucin polymer content in the adherent colonic mucus gel. , 1995, Biochemical Society transactions.

[36]  G. Kauffman,et al.  Gastric gel mucus thickness: effect of distention, 16,16-dimethyl prostaglandin e2, and carbenoxolone. , 1981, Gastroenterology.

[37]  L. Turnberg,et al.  Studies of the 'mucus-bicarbonate' barrier on rat fundic mucosa: the effects of luminal pH and a stable prostaglandin analogue. , 1983, Gut.

[38]  J. Newton,et al.  Helicobacter pylori in vivo causes structural changes in the adherent gastric mucus layer but barrier thickness is not compromised , 1998, Gut.

[39]  Y. Taché,et al.  Central vagal activation increases mucus gel thickness and surface cell intracellular pH in rat stomach. , 1997, Gastroenterology.

[40]  J. G. Forte,et al.  Salivary, gastric, pancreatic, and hepatobiliary secretion , 1989 .

[41]  A. Allen,et al.  Gastroduodenal mucosal protection. , 1993, Physiological reviews.

[42]  L. Holm,et al.  Acid transport through channels in the mucous layer of rat stomach. , 2000, Gastroenterology.