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.
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Selected References
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