In the beam-walking test, we found significant differences between the 90- and 120-min MCAO groups in the number of foot faults made with the impaired hindlimb on post-stroke days 3, 7 and 14. In the cylinder test, a difference between the 90- and 120-min groups was observed on post-operation day 14. The responses to tactile and proprioceptive stimulation were impaired to a similar extent after 90- and 120-min MCAO in the vibrissae-evoked forelimb-placing and limb-placing tests. Moreover, we found significant memory impairment in the 120-min MCAO group 6 days after the acquisition trial. The brain tissue damage was significantly higher after 120-min occlusion of the MCA compared with 90-min occlusion; the infarct volumes were 13 % and 25 % of the contralateral hemispheres, respectively.
In conclusion, both the 90- and 120-min occlusion models result in a significant impairment of sensorimotor, tactile and proprioceptive function, but memory impairment is only observed in the 120-min MCAO group. The beam-walking and cylinder tests detected neurological dysfunction after the 120-min MCAO, whereas the limb-placing and vibrissae-evoked forelimb-placing tests were able to evaluate the neurological dysfunction in rats after 90- and 120-min MCAO.