Fig. 4
From: Estimation of restraint stress in rats using salivary amylase activity
Amylase activities of control (white columns) and stress (black columns) rats during experiment. The amylase activity of the stress rats at 5 weeks of age was significantly greater than that of the control rats (*P < 0.05). The activity of the stress rats after 6 weeks of age decreased compared with that of the control rats (horizontal dot bar, F 1,7 = 23.22, P < 0.01). A significant decrease in the amylase activity of the stress rats at 9, 11 and 13 week of age was observed compared with that of the control rats († P < 0.01). White and black columns indicate the amylase activity of the control and stress rats, respectively. Amylase activity was expressed in international units/ml of saliva (U/ml). Error bars SD (n = 12)