Theinfluence of the learning and memory ability after stimulation by subthalamic nucleus-deep brain stimulation in rats with Parkinson’s disease

Abstract

Objective To investigate the changes of the learning and memory ability after being stimulated by subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson’s Disease (PD) rats. Methods 60 healthy male SD rats were randomly divided into normal control group (n=15), PD group (n=15), the rats in sham stimulation group(n=15) and stimulation group (n=15). Stimulation and sham stimulation groups were planted in unilateral STN-DBS. STN-DBS in stimulation group was powered on and was stimulated 7 consecutive days at the regular time, while the rats in Sham stimulation group complied with the same process except power on the STN-DBS. The apomorphine rotation was observed at pre-stimulation、stimulation and post-stimulation. The latency to find the platform, swimming speed, swimming distance and crossing times of rats were detected with Morris water maze. Results The symptoms of PD rats were improved significantly after stimulated by STN-DBS. Compared with PD model group and sham stimulation model group, not only escape latency of rats in the DBS stimulated model group was decreased (P=0.008, P=0.009), but also swimming speed (P=0.002, P=0.001) and swimming distance (P=0.091, P=0.001) were descend. The crossing times、the percentage swimming distance and the percentage swimming time in which the platform located of PD model group [respectively (1.380±1.193) times, (19.470±3.226)%, (18.766±5.486)%] and sham stimulation model group [respectively (1.730±1.009) times, (19.862±4.125)%, (21.846±4.234)%] were definitely lesser than stimulation model group [respectively (6.800±1.135) times, (28.010±4.113)%, (31.836±9.940)%]. In terms of the crossing times(P=0.003, P=0.022), the percentage swimming distance (P=0.011, P=0.014) and the percentage swimming time (P=0.016, P=0.021) in the platform, there were significant differences that stimulation model group compared with PD model group and sham stimulation model group. Conclusion STN-DBS stimulation can not only improve the ability of cognition, but also delay the condition worsen. Key words: Parkinson’s disease; Cognition; Morris water maze; Subthalamic nucleus-deep brain stimulation; Rats