Chronic ethanol feeding and microvillus membrane glycosylation in normal and protein-malnourished rat intestine.
Ethanol feeding to rats for 40 days enhanced (p < 0.001) the activities of alkaline phosphatase, sucrase, gamma-glutamyltransferase (GTP), and p-nitrophenyl (PNP)-beta-D-galactosidase (p < 0.05) with no change in leucine amino peptidase (LAP) and PNP-beta-D-glucosidase activities in intestine compared with control rats. The activities of alkaline phosphatase, sucrase, and GTP were diminished (p < 0.01) in ethanol-fed malnourished rats. There was no change in LAP activity, but the levels of glucosidase and galactosidase were elevated under these conditions. Brush-border sialic acid, fucose, hexose, and hexosamine contents were elevated in ethanol-fed protein-deficient animals. Ethanol administration to normally fed rats elevated the membrane sialic acid and hexose contents, reduced fucose content, and had no effect on brush-border hexosamine content compared with the control group. These results are in agreement with data on lectin binding to brush borders under these conditions. Alcohol ingestion reduced the incorporation of [14C]-glucosamine into brush borders in rats maintained on an 18% protein diet but augmented the incorporation of [14C]-glucosamine and [14C]-mannose in protein-malnourished membranes. These observations suggest that nutrition status influences the sensitivity of microvillus membrane glycosylation to ethanol feeding in rat intestine.
Department of Biochemistry, Panjab University, Chandigarh, India.
J
J
Kaur
V M
VM
Jaswal
J P
JP
Nagpaul
A
A
Mahmood
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D004044:Dietary Proteins / Q000008:administration & dosage; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D005643:Fucose / Q000378:metabolism; D005944:Glucosamine / Q000378:metabolism; D006031:Glycosylation; D006160:Guanosine Triphosphate / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D008358:Mannose / Q000378:metabolism; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism*; D019158:N-Acetylneuraminic Acid; D011488:Protein Deficiency / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012794:Sialic Acids / Q000378:metabolism; D013393:Sucrase / Q000378:metabolism; D001616:beta-Galactosidase / Q000378:metabolism; D005723:gamma-Glutamyltransferase / Q000378:metabolism
D004044:Dietary Proteins; D006601:Hexoses; D012794:Sialic Acids; D005643:Fucose; D000431:Ethanol; D006160:Guanosine Triphosphate; D005723:gamma-Glutamyltransferase; D000469:Alkaline Phosphatase; D001616:beta-Galactosidase; D013393:Sucrase; D019158:N-Acetylneuraminic Acid; D005944:Glucosamine; D008358:Mannose