Fig. 5. Effects of chlorate and BzlGalNAc on basal and stimulated secretion of newly made proteins. (A) Phosphorimage of secreted [³⁵S]met/cys-labeled proteins. Pulse-labeled acini were washed and chased at 1 mg cell protein per ml in the indicated buffers. During the final 30 minutes of chase, 1 µM carbachol and 1 mM 8-Br-cAMP were added to stimulate regulated secretion (S). The lane marked `0' is 10% of a time zero pellet (0 hour chase) used to quantify the percentage release values. (B) The effect of 30 mM chlorate on basal and stimulated secretion (arrow indicates addition of stimulus for final 30 minutes of chase) of [³⁵S]met/cys-labeled proteins. Amylase release was quantified relative to cell content just after the pulse labeling. Data are means±s.e., n=4 independent experiments. (C) The effect of 32 mM BzlGalNAc on basal and stimulated secretion (arrow indicates addition of stimulus for final 30 minutes of chase) of [³⁵S]met/cys-labeled proteins. For comparison, the control data from panel B are reproduced here. Data are means±s.e.m., n=4 independent experiments. ^*P=0.005 compared with the DMSO control after stimulation. (D) Quantification of basal and stimulated secretion (arrow indicates addition of stimulus for final 30 minutes of incubation) of prestored protein by Coomassie blue staining of secreted media from a representative independent experiment. (E) Quantitation of [³⁵S]labeled amylase 6 hours after chase under the different conditions. Data are expressed as a percentage of initial level of labeled amylase; means±range of values from two independent experiments.

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