Efficacy of elevated body swing test in the early model of Parkinson's disease in rat.

Animal models of Parkinson's disease (PD) with partial damage of the dopaminergic nigrostriatal system are very suitable for the development of neuroprotective and neurotrophic treatment strategies. Although drug-induced rotational behavior has conventionally been used for the analysis of lesioned animals, a pure behavioral test that can evaluate such animals in a drug-free state may better reflect a more natural response following lesion. In this study, an early model of PD was developed by intrastriatal injection of 12.5 microg of 6-hydroxydopamine (6-OHDA) into the left striatum. Apomorphine-induced rotational and drug-free elevated body swing behaviors were evaluated. The results of the rotational test revealed a very significant contralateral turning in the rats of the lesion group (L+V) compared with the sham-operated group (SH) (P<.0001). In addition, the results of elevated body swing test (EBST) showed a significant difference between the L+V and SH groups in the second (P<.01) and fourth weeks (P<.05) after surgery. Further analysis of correlation for the net number of rotations versus the net number of swings revealed a significant and positive correlation (r=.52) in the second week in the L+V group, but no such correlation was observed in the fourth week (r=.24). Taken together, it is concluded that despite a poor correlation at fourth week postlesion, EBST itself may be appropriate and sensitive for the evaluation of motor asymmetry in the unilateral model of early PD in rats.