Ileal

Dietary deficiency in the absence of absorption defects can be effectively reversed with oral supplementation of 1 p.m of vitamin B 2 daily. If deficiency is related to a defect in vitamin absorption, daily doses of 1 pg adininistered subcutaneously or intramuscularly are effective (33). However, a single intramuscular dose of 100 pg of cobalamin once per month is adequate in patients with chronic gastric or ileal damage. Larger doses are generally rapidly cleared from the plasma into the urine and are not effective unless the patient demonstrates poor vitamin retention. 

Figure 9 Relative accuracy of comparative models. Upper left panel, comparison of homologous structures that share 40% sequence identity. Upper right panel, conformations of ileal lipid-binding protein that satisfy the NMR restraints set equally well. Lower left panel, comparison of two independently determined X-ray structures of interleukin 1(3. Lower right panel, comparison of the X-ray and NMR structures of erabutoxin. The figure was prepared using the program MOLSCRIPT [236].

FIGURE 5.19 Method of Barlow for measurement of affinity of a partial agonist, (a) Guinea pig ileal smooth muscle contraction to histamine (filled circles) and partial histamine receptor agonist E-2-P (N,N-diethyl-2-(l-pyridyl)ethylamine (open circles). Dotted lines show equiactive concentrations of each agonist used for the double reciprocal plot shown in panel b. (b) Double reciprocal plot of equiactive concentrations of histamine (ordinates) and E-2-P (abscissae). Linear plot has a slope of 55.47 and an intercept of 1.79 x 10s. This yields a KB (1 — tp/ta) = 30.9 pM. (c) Variant of double reciprocal plot according to Equation 5.8. (d) Variant of double reciprocal plot according to Equation 5.10. Data redrawn from [10],... 

A dose-response curve to a full agonist is obtained. Shown for this example (see Table 12.4) are data to the full agonist histamine in guinea pig ileal smooth muscle (responses as a percentage of the maximal response to histamine). 

Baringhaus KH, Matter H, Stengelin S and Kramer W. Substrate specificity of the ileal and the hepatic Na /bile acid cotransporters of the rabbit. II. A reliable... 

D QSAR pharmacophore model for the ileal Na /bile acid cotransporter. J Lipid Res 1999 40 2158-68. 

MARIOTTI F, MAKE S, BENAMOUZIG R, LUENGO 0, DARE S, GAUDICHON 0, TOME D (1999) Nutritional value of [15N]-soy protein isolate assessed from ileal digestibility and postprandial protein utilization in humans. /AmZ 129 1992-7. 

RAVINDRAN V, CABAHUG s, RAVINDRAN G, BRYDEN w L (1999) Inflnence of microhial ph)dase on apparent ileal amino acid digestibility of feedstuff s for hroUers. Poult Sci. 78 699-706. 

FAHEY G c Jr (2002a) Supplemental fructooligosaccharides andmannanoUgosaccharides influence immune function, ileal and total tract nutrient digestibilities, microbial populations and concentrations of protein catabolites in the large bowel of dogs. J Nutr 132 980-9. 

Grisham, M.B., Gaginella, T.S., Ritter, C.V., Tamai, H., Be, R.M. and Granger, D.N. (1990b). The effects of neutrophil-derived oxidants on ileal mucosal permeability, electrolyte transport and epithelial cell viability in the rat. Inflammation 14, 531-542. 

Antibiotics have been studied based on the rationale that they may interrupt the inflammatory response directed against endogenous bacterial flora. Metronidazole and ciprofloxacin have been the two most widely-studied agents.32 Metronidazole may benefit some patients with pouchitis (inflammation of surgically-created intestinal pouches) and patients with CD who have had ileal resection or have perianal fistulas. Ciprofloxacin has shown some efficacy in refractory active CD. Both drugs may cause diarrhea, and long-term use of metronidazole is associated with the development of peripheral neuropathy. 

Patients with complicated typhoid fever (i.e., metastatic foci, ileal perforation, etc.) should receive parenteral therapy with ciprofloxacin 400 mg twice daily or ceftriaxone 2000 mg once daily. Antimicrobial therapy can be completed with an oral agent after initial control of the symptoms of typhoid fever. In persons with AIDS and a first episode of Salmonella bacteremia, a longer duration of antibiotic therapy (1-2 weeks of parenteral therapy followed by 4 weeks of oral fluoroquinolone) is recommended to prevent relapse of bacteremia. 

When diabetic rabbits (24) were treated with 50 IU of bovine insulin imbibed at 50 mg/g poly (acrylic acid) (Figure 14) no reduction in serum glucose over that achieved by the dry blend control could be detected. Pretreatment of the animals with oral doses of either a penetration enhancer, sodium taurocholate, or a protease inhibitor, aproteinin, failed to improve the insulin activity. One possible explanation for this unexpected lack of activity might be that the diseased animals exhibit impaired ileal absorption of fluids (25). 

SM Schwartz, HE Bostwick, MS Medow. Estrogen modulates ileal basolateral membrane lipid dynamics and Na+-K+ ATPase activity. Am J Physiol 254 G687-G694, 1988. 

M Bendayan, E Ziv, R Ben-Sasson, H Bar-On, M Kidron. Morpho-cytochemical and biochemical evidence for insulin absorption by the rat ileal epithelium. Diabeto-logia 33 197-204, 1990. 

Figure 38 Correlations between appearance permeability coefficients for a related series of peptides measured in mesenteric blood draining perfused rat ileal segments and Caco-2 cell monolayers in the Transwell system. See Table 14 for identification of the peptides. The Pe for the rat ileum was not corrected for the aqueous boundary layer and blood flow effects. [Redrawn from Kim et al. (1993) with permission from the publisher.]...

Several of the postulated roles for nematode-secreted AChEs assume that they gain access to the intestinal mucosa. Several possibilities exist for transport of parasite AChE across the epithelial cell barrier, such as (i) utilization of existing pathways for receptor-mediated transcytosis (ii) a paracellular route facilitated by parasite-secreted proteases as observed for a bacterial elastase (Azghani et al., 1993) and (iii) increased paracellular permeability resulting from inflammatory events in the mucosa. We consider the latter suggestion most likely, as this has been duplicated by ex vivo perfusion with rat mast cell protease II (Scudamore et al., 1995). Moreover, cholinergic stimulation attenuates epithelial barrier properties to macromolecules in rat ileal crypts (Phillips et al., 1987). 

Phillips, T.E., Phillips, T.L. and Neutra, M.R. (1987) Macromolecules can pass through occluding junctions of rat ileal epithelium during cholinergic stimulation. Cell and Tissue Research 247, 547-554. 

Shneider, B. L., et al. Cloning and molecular characterization of the ontogeny of a rat ileal sodium-dependent bile acid transporter. J. 

Wong, M. H., P. Oelkers, and P. A. Dawson. Identification of a mutation in the ileal sodium-dependent bile acid transporter gene that abolishes transport activity. J. Biol. Chem. 1995, 270, 27228-27234. 

Hara, S., et al. S-8921, an ileal Na+/ bile acid cotransporter inhibitor decreases serum cholesterol in hamsters. Life Sci. 1997, 60, 365-370. 

Root, C., et al. Ileal bile acid transporter inhibition, CYP7A1 induction, and antilipemic action of 264W94. 

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