ABSTRACT
Objective To explore the effect of the treadmill exercise intervention on the behavior function and the concentration of dopamine in the striatum of the rat model of Parkinson's disease (PD).Methods Healthy male Sprague-Dawley rats were randomly divided into a sham operation quiet (Control) group,sham-operation+Exercise (Control + Ex) group,6-hydroxydopamine (6-OHDA) quiet (PD) group,and 6-OHDA+Exercise (PD + Ex) group.PD and PD + Ex groups were injected 6-OH-DA into the right medial forebrain bundle to establish the unilateral PD rat model,while the sham operation groups were injected the same amount of physiological saline at the same site.On the 7th days after modeling,the rats were subcutaneously injected Apo morphine for rotational behavior test to exclude those not meeting the requirements for the PD model.One week after the operation,the exercise group started treadmill training at the speed of 11 m/min,30 min/day and 5 days/week,for a total of four weeks.The locomotor activity of PD rats was evaluated using the open field test.The DA concentration in striatum was detected using micro dialysis high performance liquid chromatography and electrochemistry.The expression of tyrosine hydroxylase positive fiber in the striatum was assessed using the immunohistochemistry.Results Compared with the Control group,significant decrease was observed in the moving distance of PD and PD + Ex groups (P＜0.01),while significant increase was found of PD + Ex group compared with PD group after 3 and 4weeks of training (P＜0.01).Compared with the Control group,DA concentration in the striatal decreased significantly in PD and PD + Ex groups,but that of PD + Ex group increased significantly after 3 and 4weeks' training compared with the PD group (P＜0.01).Conclusion There is a highly positive correlation between the total moving distance and the DA concentration in the striatum of PD rats.The moving distance and the DA concentration both have changed "sequentially" with the prolongation of 6-OHDA and exercise intervention.The exercise intervention can reduce the DA loss of the striatum and improve the locomotor function of PD rats.It is presumed that the mechanism may be related to the neuroprotective effect of exercise,which can reduce the damage of 6-OHDA neurotoxin to DA neurons and promote their survival.