Figure 1.

Effect of Dex on CBE activity in isolated mouse SMG cells and fluid secretion in sealed parotid ducts. (A,B) Localization of α2_A-adrenergic receptor (AR) in SMG tissue and isolated SMG acini. (C) Protein expression α2_A-AR in SMG. CBE activity was determined by measuring changes in pH_i in SMG acini (D), SMG ducts (E), and parotid acini (F) with and without 100 ng/ml Dex. The slope of pH_i measured CBE activity in the absence of Cl⁻ at the beginning of time course (30–45 s), and height to reach the point of maximum pH_i from the minimum point. Bars represent the mean ± SEM (n = 4, ^*p < 0.01, #p < 0.05). (G) Sealed parotid ducts were isolated and used to measure fluid secretion in response to stimulation with 5 μM forskolin in the absence (control, open square) and presence of 100 ng/ml Dex (closed rhombus) (n = 4, ^*p < 0.01). (H) The mean ± SEM at the 40 min secretion time point shows an increase in basal secretion upon Dex treatment.