Dopamine transporter shown by SPECT in patients with periodic leg movement after acute physical exercise.

Purpose: This study aimed to evaluate dopamine transporter (DAT) density in patients with periodic leg movement (PLM) shown by [(99mt)Tc]TRODAT-1 single-photon emission computed tomography (SPECT) imaging and to determine the influence of acute physical exercise (maximal exercise test [MET]) on DAT densities.

Methods: Sixteen healthy male volunteers between 45 and 65 yr of age were selected to participate in the study. Each subject (eight subjects in the control group and eight subjects in the patients with PLM experimental group) underwent baseline polysomnography (PSG) to evaluate sleep patterns and PLM index values. After obtaining PSG baselines, SPECT baselines were determined using [(99mt)Tc]TRODAT-1, a selective DAT imaging ligand. Subsequently, the volunteers performed the MET in the morning, followed by a SPECT 2 h later and PSG that night to assess the effect of acute physical exercise on DAT and sleep patterns.

Results: The baseline SPECT results showed marginally significantly lower DAT densities in the striatal region of the experimental group. After the MET, no significant differences were observed between groups. The results also showed a significant reduction in the PLM index in the experimental group and a significantly increased percentage of stage 1 non-REM sleep in both groups after MET.

Conclusions: Our results show that patients with PLM had a marginally lower DAT density in the left putamen region compared with the control group. Although the effect of acute physical exercise (MET) reduced PLM symptoms, the results suggest that this improvement was not due to DAT availability.