Fig. 11. Changes in the level of salivation upon electrical stimulations of one salivary duct nerve (SDN). The amount of saliva secreted from a salivary duct was measured every minute while brief (0.2 ms) electric pulses were delivered to the SDN at 5 Hz for 2, 5, 10, 20 and 40 s with intervals of 6 min. Averaged data from 12 preparations are shown as means ± s.e.m. The amounts of secretion (broken lines) before and after the onset of electrical stimulation were statistically compared, and asterisks indicate the level of significance (^*P<0.05; ^**P<0.01; WCX-test).