TY - JOUR
T1 - On the transfer of serum proteins to the rat intestinal juice.
AU - Andersen, Vibeke
AU - Norén, Ove
AU - Poulsen, Mona D
AU - Sjöström, H
AU - Hansen, Gert Helge
AU - Olsen, Jørgen
N1 - Keywords: Animals; Biological Transport; Blood Proteins; Immunoelectrophoresis, Two-Dimensional; Immunoglobulins; Immunohistochemistry; Intestinal Mucosa; Intestinal Secretions; Male; Molecular Weight; Orosomucoid; RNA; Rats; Rats, Wistar; Serum Albumin; Transferrin; alpha 1-Antitrypsin
PY - 1994
Y1 - 1994
N2 - The in vivo pattern of serum proteins in the rat small-intestinal juice was characterized by crossed immunoelectrophoresis. Immunoglobulins and albumin, alpha-1-antitrypsin, transferrin, and orosomucoid were present. Larger serum proteins were absent (ceruloplasmin, haptoglobin, alpha-1-macroglobulin, alpha and beta lipoproteins). Thus, apart from immunoglobulins, only serum proteins with a molecular mass less than approximately 100 kDa were demonstrated. The origin and epithelial transfer were further characterized, using albumin as a model. No sign of local synthesis of albumin by the enterocytes was found by Northern blotting, and no albumin was found in the Golgi complex by immunogold electron microscopy. By immunogold electron microscopy a heavy labelling of albumin was observed in the interstitial spaces between the villus enterocytes. Where the enterocytes disintegrated, albumin was seen to leak out into the intestinal lumen from the opened interstitial spaces. A weak labelling was also found in the lysosomal/endosomal-like structures, especially in the crypt enterocytes, indicating pinocytosis of albumin. We conclude that the main reason for the occurrence of certain serum proteins in the intestinal juice is a selective passage through the capillary wall followed by passive intercellular transport via delivery of the serum in the interstitial space during disintegration of the enterocytes.
AB - The in vivo pattern of serum proteins in the rat small-intestinal juice was characterized by crossed immunoelectrophoresis. Immunoglobulins and albumin, alpha-1-antitrypsin, transferrin, and orosomucoid were present. Larger serum proteins were absent (ceruloplasmin, haptoglobin, alpha-1-macroglobulin, alpha and beta lipoproteins). Thus, apart from immunoglobulins, only serum proteins with a molecular mass less than approximately 100 kDa were demonstrated. The origin and epithelial transfer were further characterized, using albumin as a model. No sign of local synthesis of albumin by the enterocytes was found by Northern blotting, and no albumin was found in the Golgi complex by immunogold electron microscopy. By immunogold electron microscopy a heavy labelling of albumin was observed in the interstitial spaces between the villus enterocytes. Where the enterocytes disintegrated, albumin was seen to leak out into the intestinal lumen from the opened interstitial spaces. A weak labelling was also found in the lysosomal/endosomal-like structures, especially in the crypt enterocytes, indicating pinocytosis of albumin. We conclude that the main reason for the occurrence of certain serum proteins in the intestinal juice is a selective passage through the capillary wall followed by passive intercellular transport via delivery of the serum in the interstitial space during disintegration of the enterocytes.
M3 - Journal article
C2 - 7518612
SN - 0036-5521
VL - 29
SP - 430
EP - 436
JO - Scandinavian Journal of Gastroenterology
JF - Scandinavian Journal of Gastroenterology
IS - 5
ER -