Pancreatic Extract and the Intestinal Uptake of Vitamin B₁₂

Abstract

Pancreatic extract (PE) contained small-molecular, thermo-stable as well as macro-molecular, thermo-labile factors capable of reducing the uptake of ⁵⁷CoB₁₂ bound to rat intrinsic factor by perfused rat intestinal segments (p<0.01 and p<0.01). Neither non-radioactive vitamin B₁₂ nor non-pancreatic protein reduced the ⁵⁷CoB₁₂-uptake (p>0.5 and p>0.1). Crystalline trypsin and trypsinogen, but not chymotrypsin, also inhibited the uptake (p<0.05, p<0.02 and p>0.05). The tryptic inhibition was abolished by soybean trypsin inhibitor (p>0.05).

Key-words:

• Chymotrypsin
• intestinal secretions
• pancreatic disease
• pancreatic extract
• trypsin
• trypsin inhibitor
• trypsinogen
• vitamin B₁₂
• vitamin B₁₂ deficiency