title: Involvement of gamma-glutamyltransferase in amino-acid uptake by the lactating mammary gland of the rat.
abstract: 1. Arteriovenous differences of amino acids across the lactating mammary gland have been measured in normal rats and in rats injected with serine--borate (an inhibitor of gamma-glutamyltransferase). 2. Comparison of the arteriovenous differences show that gamma-glutamyltransferase is involved in amino-acid uptake by the gland. 3. Reduced-glutathione content of isolated acini incubated with high concentrations of amino acids was lower than that of the controls. 4. High concentrations of amino acids had no effect on reduced-glutathione content of isolated acini when serine--borate was added to the incubation medium. 5. The findings provide evidence for the functioning of the gamma-glutamyl cycle in the lactating mammary gland in vivo.
mesh_terms: D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001881:Borates / Q000494:pharmacology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D007774:Lactation; D008321:Mammary Glands, Animal / Q000201:enzymology*; D011247:Pregnancy; D051381:Rats; D012694:Serine / Q000494:pharmacology; D005723:gamma-Glutamyltransferase / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D001881:Borates; D012694:Serine; D005723:gamma-Glutamyltransferase; D005978:Glutathione