Beam-walking test.

A beam-walking test was used to assess the coordination and integrity of motor movements^60–62. The time taken to cross the beam and the number of left and right paw slips were recorded with a video camera and analyzed by an experimenter blinded to the treatment groups. The Plexiglas beam was 100-cm long and 0.5-cm wide and was elevated 50 cm off the floor leading to the motivation box (MB) which was 20 cm (length) x 20 cm (width) x 20 cm (height) and made of black plastic. Mice were given five trials of training to learn to traverse the beam. During the first training trial, the animal was placed 25 cm away from the MB; the second trial began at 50 cm away from the MB; on the third, fourth and fifth trials, the animal was placed at the starting point 100 cm away from the MB. On the testing days, mice were given three trials to traverse the beam. The testing days occurred before MCAo and on Day 7 and Day 14 post-surgery. The duration of beam traversal was defined as when the mice started walking across the beam to when the two front paws entered the MB. A maximum trial duration of 300 s was recorded for mice that failed to reach the MB.