Pancreatic extract and the intestinal uptake of vitamin B12. II. Inhibitory effect of trypsin and trypsinogen.
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 less than 0.01 and p less than 0.01). Neither non-radioactive vitamin B12 nor non-pacreatic protein reduced the 57CoB12-uptake (p greater than 0.5 and p greater than 0.1) Crystalline trypsin and trypsinogen, but not chymotrypsin, also inhibited the uptake (p less than 0.05, p less than 0.02 and p greater than 0.05). The tryptic inhibition was abolished by soybean trypsin inhibitor (p greater than 0.05).
D000818:Animals; D002918:Chymotrypsin / Q000494:pharmacology; D003956:Dialysis; D006358:Hot Temperature; D007408:Intestinal Absorption / Q000187:drug effects*; D007421:Intestine, Small / Q000378:metabolism; D007437:Intrinsic Factor / Q000378:metabolism; D008297:Male; D010184:Pancreatic Extracts / Q000494:pharmacology*; D010477:Perfusion; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D014357:Trypsin / Q000494:pharmacology*; D014362:Trypsinogen / Q000494:pharmacology*; D014805:Vitamin B 12 / Q000378:metabolism*
D010184:Pancreatic Extracts; D014362:Trypsinogen; D007437:Intrinsic Factor; D002918:Chymotrypsin; D014357:Trypsin; D014805:Vitamin B 12