The effect of gastric secretions on iron attachment to the small intestine

SUMMARYThe effects of the direction of gut flow, of injections of glucose and saline into different regions of the small intestine and of surgical re-routing or ligature of gastric, biliary and pancreatic secretions into the small intestine have been correlated with changes in the migratory response of the rat tapeworm Hymenolepis diminuta. Reversing the normal anterior to distal flow of luminal contents in the small intestine did not affect worm migration following feeding. Injections of a glucose-saline solution into the duodenum did not initiate a migratory response; similar injections into the mid- and posterior regions of the small intestine resulted in migrational responses similar to those following intragastric glucose feeding. Re-routing gastric secretions to the distal duodenum inhibited anterior migration of the worms beyond the new point of entry of gastric juices. Results following re-routing and ligation of the biliary and pancreatic secretions suggest that there is a potent cue to anteriad migration in the pancreatic secretions. Biliary secretions also appear to contain an additional migratory cue to worm migration. In order of importance the factors stimulating/inhibiting worm migration are pancreatic > gastric > biliary > glucose. The results support the hypothesis that the factors affecting worm distribution in the small intestine are interactive and synergistic, involve other luminal factors, such as 5- hydroxytryptamine and the physico-chemical gradients, and are of a regional nature such that the migratory response of a particular worm is directly related to its position in the small intestine when the cues to relocation are received.

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Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142311 ◽

1986 ◽

Vol 44 ◽

pp. 134-135

Author(s):

A. J. Tousimis

Keyword(s):

Small Intestine ◽

Amino Acid ◽

Epithelial Cells ◽

Elemental Composition ◽

Isotope Labeling ◽

Structural Components ◽

X Ray ◽

Human Small Intestine ◽

Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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The protease phenotype and crystalline nature of the granules of intraepithelial mast cells in Trichinella spiralis-infected mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140464 ◽

1995 ◽

Vol 53 ◽

pp. 818-819

Author(s):

D.S. Friend ◽

N. Ghildyal ◽

M.F. Gurish ◽

K.F. Austen ◽

R.L. Stevens

Keyword(s):

Small Intestine ◽

Mast Cells ◽

Epithelial Cells ◽

Lamina Propria ◽

Trichinella Spiralis ◽

Intestinal Epithelial ◽

Carboxypeptidase A ◽

C3h Mice ◽

Granule Morphology ◽

Crystalline Nature

Trichinella spiralis induces a profound mastocytosis and eosinophilia in the small intestine of the infected mouse. Mouse mast cells (MC) store in their granules various combinations of at least five chymotryptic chymases [designated mouse MC protease (mMCP) 1 to 5], two tryptic proteases designated mMCP-6 and mMCP-7 and an exopeptidase, carboxypeptidase A (mMC-CPA). Using antipeptide, protease -specific antibodies to these MC granule proteases, immunohistochemistry was done to determine the distribution, number and protease phenotype of the MCs in the small intestine and spleen 10 to >60 days after Trichinella infection of BALB/c and C3H mice. TEM was performed to evaluate the granule morphology of the MCs between intestinal epithelial cells and in the lamina propria (mucosal MCs) and in the submucosa, muscle and serosa of the intestine (submucosal MCs).As noted in the table below, the number of submucosal MCs remained constant throughout the study. In contrast, on day 14, the number of MCs in the mucosa increased ~25 fold. Increased numbers of MCs were observed between epithelial cells in the mucosal crypts, in the lamina propria and to a lesser extent, between epithelial cells of the intestinal villi.

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