Figure 4.

Post-stroke treatment with Tat-K13 peptide improves motor behavioral performances after a focal ischemic brain insult in vivo. Focal ischemia and peptide applications were as described in Figure 3 (n = 10 in each group). A, Biased body swing tests revealed that animals receiving post-stroke treatment of Tat-K13 (both 2 and 6 h groups) exhibited a much faster recovery than those treated with saline or control peptides over the 4 week recovery period following stroke. B, Tat-K13 peptide, but not its control peptides, dramatically promoted the locomotor activity recovery of the stroke rats in comparison with saline treatment. The locomotor activity (vertical movement time) was automatically measured using a computerized locomotor box within a 2 h observation period over the 4 week recovery period following stroke. C, The grip strength test showed that animals receiving Tat-K13 treatments (both 2 and 6 h groups) had a much better grip strength performance than those receiving control peptides or saline at 28 d after stroke. Together, these behavioral tests suggest a long-lasting therapeutic effect of Tat-K13 peptide on improving the motor functions. Bars represent the group means, and error bars represent SD. Post hoc analysis compares treatment groups with control (saline) group after significant one-way ANOVA or Kruskal–Wallis on ranks, and significance is defined as *p < 0.05, **p < 0.01.