A novel method for kinetic study identifies age and sex specific differences in reflex-saliva flow in preclinical model. Workflow to measure pilocarpine-stimulated saliva flow by Schirmer's test strips and gravimetry (panel A). X-Y plot showing correlation between gravimetric method vs. Schirmer's test based detection of pilocarpine-stimulated saliva fraction in 19 young male (panel B) and 20 young female (panel C) precision-irradiated NSG-SGM3 mice. Cumulative Gaussian plot comparing young and old female mice (panel D) and age-matched male and female (young NSG-SGM3) mice (panel E). ***P < 0.0001, ns = not significant. Kinetics of pilocarpine-stimulated saliva flowrate (µg/min) in 3 week after sham-treated 5 young and 4 old female NSG-SGM3 mice (panel F) and in prior-to-sham/radiation-treated 20 male and 20 female young NSG-SGM3 mice (panel G). Plot showing sex- and age-specific differences in means of saliva flowrate at 10 and 25 mins after stimulation in young and old female mice shown in panel F (panel H) and in male and female mice in panel G (panel I). * P < 0.01.