Measurement of stimulated saliva flow

Each NOD mouse was first anesthetized with an i.p. injection of pentobarbital (25 mg/kg/body weight, Sigma-Aldrich, USA) and a subsequent i.p. injection of pilocarpine (1.0 mg/kg/body weight, Leqi, Wuhan). At 1 min after injection of the secretagogue, saliva was collected from the oral cavity using a 200-μl micropipette for 15 min at room temperature. The volume (μl) of each saliva sample was measured and expressed relative to body weight (grams). Baseline saliva flow rates were measured 3 days before the drug injection, and final saliva flow rates in each group were measured the end of the drug injection.