Fig. 2.

PRS effects on striatum-dependent behaviors in adulthood and during aging.

In the active avoidance test (Fig. 2A), PRS reduced the conditioned responses and box switches (n = 6–7 adult rats/group). Four-month-old adult PRS male rats also showed defective striatal motor performance in the grip strength test (Fig. 2B) by displaying reduced strength over three consecutive days of training (n = 6 adult rats/group). Aging (21 months) induced defective striatal motor performance only in the ladder rung-walking test (n = 6 rats/group, Fig. 2C), in which 21-month-old aged rats showed more errors than did 4-month-old adult rats. While a PRS effect was observed in both age groups, 21-month-old PRS rats showed more errors in the ladder rung-walking test. In the pasta matrix-reaching test (Fig. 2D), PRS affected both age groups. PRS rats removed a lower number of pasta pieces than unstressed control rats, with consequently poorer extension of the matrix for PRS rats than for unstressed control rats (n = 6–7 rats/group). In addition, in the elevated plus maze test (Fig. 2E), PRS rats of both ages showed lower exploration of the open arm and consequent risk-taking behaviors (n = 7 rats/group). CONT vs. PRS *p < 0.05; **p < 0.01; ***p < 0.001; adult vs. aged ### = p < 0.001.