[Comparative study on the digestion of radiolabelled vicilin, legumin and lectin of Pisum sativum in the rat].

Storage proteins, vicilin, legumin as well as the lectin, purified from pea seed proteins, were radiolabelled with [14C]- or [3H]-formaldehyde, then mixed with the pea flour which was incorporated in a liquid meal and given to rats through a gastric tubing. Radiolabelled casein (75% of the total proteins in the meal) and triolein were added to the meal and the animals were killed after 2 and 7 h. Samples were taken from the stomach and intestinal contents and from the intestinal mucosa and the liver. 2 h: gastric emptying and intestinal absorption from vicilin and legumin materials were as high as for casein. 7 h: in the colon contents an excess of labelled vicilin and legumin (2.9 and 2.6% of the radioactive dose from the meal) was observed compared to casein (1.5%). The pea lectin disappeared slowlier from the intestinal contents than did the three other radiolabelled proteins (2 h) which gave the highest radioactive materials in the livers. The lectin did not interact with the intestinal mucosa but it was less hydrolysed than the three other proteins tested and 15% of the dose reached the colon (7 h). This lectin could have been adsorbed on pancreatic enzymes such as a lipase, but radiolabelled triolein did not produce radioactive material in the colon, demonstrating that lectin or other pea proteins, in these experiments did not inhibit this lipase. Short-time experiments (2 h, 7 h) were sufficient to describe and compare the digestion of three radiolabelled pea proteins.