Specificity and inhibition of gamma-glutamyl transpeptidase in guinea pig intestines.
Gamma-Glutamyl transpeptidase activity in guinea pig intestine was tested toward 8 monoglutamyl and 4 diglutamyl substrates. Distinct differences in specificity and activity related to ontogenetic development were noted. A mixture of L-serine and borate inhibited specifically gamma-glutamyl transpeptidase activity of homogenates and accumulation of naphthylamine and 14C-substances in slices of intestine incubated with gamma-L-14C-glutamyl-alpha-naphthylamide. The same mixture, administered per os together with 14C-gamma-glutamyl substrate, specifically inhibited urinary excretion of 14C-substance, but had no effect on the rate of excretion of glycine, L-glutamic acid or L-pyroglutamic acid.
D000367:Age Factors; D000818:Animals; D001881:Borates / Q000494:pharmacology; D005260:Female; D006168:Guinea Pigs; D007413:Intestinal Mucosa / Q000201:enzymology; D008297:Male; D012694:Serine / Q000494:pharmacology; D005723:gamma-Glutamyltransferase / Q000037:antagonists & inhibitors / Q000378:metabolism*
D001881:Borates; D012694:Serine; D005723:gamma-Glutamyltransferase