Catwalk-assisted behavioral analysis of rat models of middle cerebral artery occlusion

Objective To investigate the feasibility of Catwalk-assisted system in analyzing the behavioral features of rat models of middle cerebral artery occlusion(MCAO).Methods Thirty male SD rats were randomly assigned to experimental group and control group.Suture-occluded method was used to establish the focal cerebral ischemia/reperfusion models in the experimental group.Traditional modified neurological severity scale(mNSS),vibrissae-evoked forelimb placing test and cylinder test were employed to analyze the behavioral characteristics of the SD rats 1,3,7,14 and 28 dafter establishment of rat models.Besides that,Catwalk-assisted gait analysis system was employed at the same time points.Results Catwalk-assisted gait analysis results suggest rats from experimental group had smaller intensity,print area and slower walk speed than rats from control group.Besides that,interlimb coordination also changed on the 3rd d of operation and existed until the 28th d of operation.Rotate step patterns like Ra(1.5％)and Rb(2.3％)were detected in experimental group but never seen in control group.Parameters as cadence,stance,swing and other regularity index had no significant changes between the 2 groups.Conclusion Catwalk analysis system,by analyzing such movement parameters of MCAO rats as intensity,speed,print area,step pattern and interlimb coordination,can commendably reflect the damage of brain ischemia and its changes crossing time,which can comprehensively analyze many behavioral features of the models. Key words: Catwalk-assisted gait analysis system;  Cerebral ischemia;  Behavioral study