SELECTED HORMONAL EFFECTS ON PROTEIN SECRETION AND AMINO-ACID UPTAKE BY ACINI FROM BOVINE MAMMARY-GLAND

1. 1. Release of newly synthesized proteins from acini freshly isolated from lactating bovine (Bos taurus) mammary tissue was inhibited by cycloheximide. Millimolar concentrations of the cyclic AMP phosphodiesterase inhibitor theorphylline also inhibited release of protein from acini. 2. 2. Addition of either insulin or dibutyryl cyclic AMP to incubation medium stimulated release of newly synthesized protein from acini. Combinations of insulin and dibutyryl cyclic AMP were more effective than either alone. 3. 3. Cycloheximide inhibited uptake of the nonmetabolizable amino acid, 1-aminocyclopentane carboxylic acid (cycloleucine), by bovine mammary acini. Uptake of this amino acid was stimulated by inclusion of insulin and/or dibutyryl cyclic AMP in incubation medium. © 1979.