Dados do Trabalho

Título

Behavioral and molecular evaluation of the dopaminergic system in an animal model of restless legs syndrome induced by 6-OHDA in dopaminergic nucleus A11

Introdução

Investigations of the characteristics of restless legs syndrome (RLS) in humans are reproducible in animal models and present well-characterized pathophysiological mechanisms and can clarify answers for future treatments. Reproduction of behavioral aspects of RLS in animal models is difficult, knowing that disease characteristics are subjective sensory factors. However, rodent models can show behavioral changes such as increased locomotor activity. Stands out the model animal of lesion in the A11 dopaminergic nuclei with 6 hydroxydopamine (6-OHDA), which mimics characteristics related to the syndrome.

Objetivo

To evaluate the motor behavior and expression of genes and proteins of the dopaminergic system in an animal model of RLS induced by 6-OHDA in dopaminergic nucleus A11.

Métodos

The guidelines of animal ethical principles were approved by the CEUA of UNICAMP (n°4726-1/(A)2018). Adult male Wistar rats (n=15) distributed into 3 groups: Control; Injury (received lesion in the A11 nucleus with 6-OHDA); SHAM (injected with PBS). The rats underwent stereotaxic surgical procedures for bilateral lesion of the A11 nucleus with 6-OHDA. For behavioral analysis, an open field test was performed before surgery and for 4 weeks after surgery. In the striatum and medulla, molecular analyzes were performed for D2, DAT, TH (RT-PCR and Western Blotting) and PTPRD (RT-PCR and indirect Elisa). Furthermore, cross sections of the A11 nucleus were evaluated by immunofluorescence. Statistical analyses of data were performed ANOVA for repeated measures and Duncan post hoc tests, p<0.05.

Resultados

The injury group showed an increase in total ambulation and rearing, 14 after the injury. After 28 days of surgery, there was no difference between the groups, in the striatum and in the medulla, in relation to the level of transcripts of the D2, DAT, TH and PTPRD genes. TH protein content was higher in medulla of the injury and SHAM groups than control. In addition, damage was observed in dopaminergic neurons of animals with damage to the A11 nucleus.

Conclusões

Taken together, these findings suggest that damage to the A11 nucleus triggers characteristic behaviors of RLS. This fact is reinforced by the changes observed in the TH level in the injury group.

Palavras-chave

Behavior, Restless legs syndrome, Motor activity.