Effect of Bile Fistulae on Vitamin B₁₂ Absorption in Rats

Abstract

To study the effect of bile on the absorption of vitamin B₁₂, choledochocolic fistulae were made in 26 rats, and 14 rats were sham-operated. Vitamin B₁₂ absorption 9 days after the operation was significantly reduced in the fistula-operated group (median, 36.4%; range, 8.3-61.4%) as compared with the sham-operated group (median, 48.5; range, 35.8-75.2). Bile instilled together with vitamin B₁₂ did not increase the absorption. In a second ‘short-term’ experiment external bile fistulae were made in 20 rats, and 10 rats were sham-operated. Vitamin B₁₂ absorption was measured 14 h after the operation, and in this experiment no reduction was found in the fistula-operated rats. This suggests that bile in the lumen of the small intestine has no direct effect on vitamin B₁₂ absorption, but absence of bile during several days may alter other factors of importance for the absorption.

Key Words:

• Bile
• rats
• vitamin B₁₂