Quantitative CatWalk analysis of gaits in rats with 6-hydroxydopamine-induced PD

Objective To investigate the probability of quantitative analysis of parkinsonian gaits in unilateral 6-hydroxyl dopamine-lesioned rats. Methods A total of 24 male Wistar rats were assigned to control group (n=6),sham-operated group (n=6) and 6-OHDA inducement group (n=12).All subjects received anesthetization and the latter 2 groups further processed with injection of equivalent volumes of normal saline and 6-OHDA into the left medial longitudinal fasciculus on the operation day,respectively. The cylinder test and Catwalk analysis were applied successively 1 week before the operation for baseline value,and 3 d, 1 and 2 weeks after the operation. Results The cylinder test indicated that the proportion of using the right forelimbs was significantly decreased as compared with that using the left forelimbs in the 6-OHDA inducement group 3 d, 1 and 2 weeks after the operation (P＜0.05), but no significant differences of using the right forelimbs were shown in the control and sham-operated counterpart (P＞0.05). Catwalk analysis showed no significant differences either on the girdle comparisons of former/hinder limbs or on pre- and post-operation comparisons of individual limbs between control and sham-operated groups (P＞0.05). In the 6-OHDA inducement group,max contact area (MCA),paw length (PL),paw width (PW) and paw area (PA) for fore girdle comparisons and MCA for hinder ones showed significant differences (P＜0.05); all the 4 parameters of right hinder limb,the PL,PW and PA of left fore limb,the PA,PL and MCA of right fore limb,the PW of left hinder limb after the operation significantly decreased as compared with those before the operation (P＜0.05). Conclusion It is applicable to detect changes in gaits of Parkinson's disease quantitatively with Catwalk analysis,especially in terms of MCA,adding new tool for further study. Key words: PD; Model, animal; Gait; CatWalk analysis; 6-hydroxyl dopamine