vitamin-b-12 and Biliary-Fistula

Topics: Bile Acids and Salts; Biliary Fistula; Biliary Tract Diseases; Cholestyramine Resin; Chylomicrons; Colloids; Colonic Diseases; Feces; Gallbladder Diseases; Gastrointestinal Diseases; Humans; Intestinal Absorption; Intestinal Fistula; Intestinal Mucosa; Lipid Metabolism; Lipids; Liver Diseases; Macromolecular Substances; Malabsorption Syndromes; Neomycin; Pancreas; Solubility; Vitamin B 12; Xylose; Zollinger-Ellison Syndrome

To investigate whether bile reduces the amount of vitamin B12 bound by intrinsic factor (IF) in the intestinal juice in vivo, choledochocolic fistulae were made in 9 rats, and 10 rats were sham-operated. Small-intestinal juice was collected 1 h after gastric instillation of 57CoB12. The percentage of 57CoB12 bound by IF in the intestinal juice was markedly increased in fistula rats (median, 86%; range, 75-91%) as compared with sham-operated rats (35%; 12-50%) (p less than 0.001). In a second experiment we investigated whether bile enhances the intestinal uptake of the IF-B12 complex. Aliquots of the radioactive intestinal juice collected from the sham- and fistula-operated rats were separately instilled into tied intestinal loops created in 19 rats. The percentage of the instilled radioactivity taken up per 10 cm of the loop was significantly higher when juice from fistula-operated rats was instilled (median, 12.4; range, 4.3-18.7) than when juice from sham-operated rats was instilled (3.3; 1.4-6.2) (p less than 0.001).

Topics: Animals; Bile; Biliary Fistula; Cobalt Radioisotopes; Common Bile Duct Diseases; Female; Intestinal Absorption; Intestinal Secretions; Intrinsic Factor; Rats; Rats, Inbred Strains; Vitamin B 12

To investigate whether vitamin B12 malabsorption in rats with choledochocolic fistulae is caused by bacterial overgrowth, we studied intestinal bacterial metabolic activity in choledochocolic fistula-operated rats, self-filling blind-loop-operated rats, and sham-operated rats. Fistula-operated rats had a moderate indicanuria compared with sham-operated ones, whereas the faecal excretion of nitrogen was unchanged. There was no difference in the amounts of radioactivity recovered in sediments of intestinal contents after an oral dose of 57CoB12, indicating unaltered bacterial uptake of vitamin B12 in fistula rats. The 14C-xylose breath test showed bacterial overgrowth in blind-loop rats only. Neomycin treatment of fistula rats diminished the excretion of indican but did not alter the absorption of vitamin B12. The results suggest moderately increased activity of indole-producing bacteria in fistula rats, but they do not support the hypothesis that vitamin B12 malabsorption is caused by bacterial overgrowth.

Topics: Animals; Biliary Fistula; Breath Tests; Feces; Female; Indican; Intestine, Small; Neomycin; Nitrogen; Rats; Rats, Inbred Strains; Vitamin B 12; Xylose