FIGURE 2.
The β-adrenergic receptor antagonist propranolol blocks the effects of isoproterenol on rat parotid acinar cells. Where indicated, cells were pretreated (or not) with propranolol (10−6 m) for 3 min before carbachol (10−5 m, 2 min) alone or preceded by isoproterenol (10−7 m, 1 min). A, cell lysates were subjected to immunoblot analysis as indicated. B, quantification of ERK phosphorylation relative to the basal control (no addition) for conditions shown in A. n = 5. *, p < 0.01 versus carbachol (no additions).