Efeito da estimulação cerebral profunda (DBS) no comportamento de camundongos, após lesão unilateral do feixe prosencefálico medial com 6-hidroxidopamina (6-OHDA), como modelo animal da doença de parkinson

Abstract

Parkinson's disease (PD) is primarily a disease of the extrapyramidal motor function caused by severe degeneration of dopaminergic neurons of the substantia nigra. The symptomatic treatment of PD with L-dopa and dopamine agonists drug prevail the therapy of this disease, and they are highly effective in treating the early stages of the disease. However, the introduction of dopaminergic drugs is associated with acute side effects. More recently, cerebral electrostimulation has been indicated as a way to reverse the motor symptoms of PD in the most serious cases, when the drug therapy does not produce the expected effects. Thus, in this study we have proposed to test the effect of deep brain stimulation of the subthalamic nucleus, in the motor behavior and no motor one in swiss mice after unilateral lesions of the medial forebrain bundle (MFB) with 6-hydroxydopamine (6-OHDA) as an animal model of PD. We used 32 swiss mice, male, weighing between 20 and 30 grams. The animals received unilateral (intracranial) saline or 6-hydroxydopamine injection in MFB, followed or not by unilateral DBS in the subthalamic nucleus. The death of the substantia nigra by 6-OHDA was used as pharmacological model of PD, being that the DBS was used as a way to reverse the symptoms of PD. The motor behavior of the animals was assessed by rotational behavior test, by the open field test concerning to the locomotor parameters, as well as tigmotaxia, self- cleaning and number of fecal boli. All of them were evaluated three weeks after the lesion, and one week after the initiation of the treatment with DBS. The lesion with 6-OHDA altered the motor behavior of the animals. However, it did not alter the non-motor behavior. We observed that the DBS did not reverse the motor behavior and no motor, although it has presented an anxiolytic effect regardless of injury. Thus, our results suggest that there is a strong relation between the modulation of the activity of the subthalamic nucleus and no motor responses, being that the DBS can be considered therapeutic potential in the treatment of non-motor disorders in the PD.