FIGURE 3.

Passive avoidance test results. Time before enter dark compartment in acquisition and retention trials at time points of 48 h (A) and 72 h (B). Y axis indicates the difference between latency time before entering the dark room in acquisition and retention sessions (delta time). All the animals entering dark compartment during acquisition trial. At the time point of 48 h after hyaluronidase injection animals from Hyal group remembered foot shock in 90% cases, while animals from Vehicle group remembered aversive stimuli only in 60% cases, but Mann–Whitney test showed no significant difference. At the time point of 72 h 100% of animals in Hyal group avoided entering the dark compartment during retention trial versus 70% of animals in Vehicle group, delta time in two groups significantly differs. Figures show mean ± SEM, N = 10 per group, ^∗p < 0.05.