Comparison of mucosal drug conjugative rates along the gastrointestinal tract of female sheep.
The comparative distribution of p-nitrophenol UDP-glucuronosyl-transferase, 1-chloro-2,4-dinitrobenzene glutathione-S-transferase and sulphamethazine N-acetyltransferase activities was studied along the gastrointestinal mucosa of female Lacaune sheep. Gastrointestinal mucosa was characterized by a very low and unequal N-acetyltransferase activity when activities were expressed per g of wet organ. The duodenum contained highest activities (4.1 nmol/g min). When results were expressed per mg of cytosolic protein, the duodenal activity (0.64 nmol/mg min) was sixfold higher than in liver (0.11 nmol/mg min). There was a lack in N-acetyltransferase activity accepting isoniazid as substrate. Glucuronosyltransferase activity was approximately threefold higher in microsomal fractions of the mucosal lining of gastric and colonic intestine (0.43-0.58 nmol/g min) than in small intestine or caecum (0.10-0.26 nmol/mg min). Concerning cytosolic glutathione S-transferase activity, two- to threefold higher activities were obtained in omasum, jejunum, duodenum and ileum (1021-2164 nmol/g min) than in other parts (341-799 nmol/g min) when results were expressed per g of wet organ. These data were compared with corresponding hepatic activities determined in the same six female sheep.
Larrieu
G
G
Laboratoire de Pharmacologie-Toxicologie, INRA, Toulouse, France.
Kaddouri
M
M
Galtier
P
P
D000085:Acetates / Q000378:metabolism*; D019342:Acetic Acid; D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000032:analysis; D046508:Culture Techniques; D003600:Cytosol / Q000201:enzymology; D004064:Digestive System / Q000378:metabolism*; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D005965:Glucuronates / Q000378:metabolism*; D020723:Glucuronic Acid; D014453:Glucuronosyltransferase / Q000032:analysis; D005978:Glutathione / Q000378:metabolism*; D005982:Glutathione Transferase / Q000032:analysis; D007413:Intestinal Mucosa / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008861:Microsomes / Q000201:enzymology; D012756:Sheep / Q000378:metabolism*
D000085:Acetates; D005965:Glucuronates; D020723:Glucuronic Acid; D001191:Arylamine N-Acetyltransferase; D014453:Glucuronosyltransferase; D005982:Glutathione Transferase; D005978:Glutathione; D019342:Acetic Acid