Figure 7. EE transiently improves functional recovery after tMCAO.

Rats were behavior tested 6 days after tMCAO to establish baseline deficits and again on days 28 and 60 after tMCAO to assess recovery. Forelimb asymmetry was assessed using the cylinder test and vibrissae-evoked placing while hindlimb asymmetry was assessed on the ledged, tapered beam. All rats displayed similar deficits on day 6 in the cylinder test (A, black bars) and beam test (B, black bars). Normal behavior in uninjured rats is 0. However, only a few animals had successful placing and in only about 10% of all trials in the vibrissae-evoked placing test (C, black bars). By day 28, all groups showed some improvement on the cylinder test (A, gray bars) but only the NML/EE group trended toward improvement (+p=0.06 vs. NML/SE). All groups except RA/SE showed some improvement on the beam test but none were significantly different (B, gray bars). RA/SE showed no improvement on the beam test (B, gray bars) but showed a slight but insignificant improvement on the vibrissae-evoked placing test (C, gray bars) while other groups showed no improvement on this test. By day 60, all groups except NML/EE displayed similar deficits on the cylinder test as were seen on day 28 (A, white bars). Interestingly, the NML/EE group had more severe deficits on the cylinder test at day 60 than at day 28 (A, white bars), suggesting that the improvements seen during the course of treatment were lost one month after treatment halted. All groups remained the same on day 60 as they were on day 28 in the beam test (B, white bars) and vibrissae-evoked placing (C, white bars).