RESUMO
We investigated the role of serotonin (5-HT) in the pathogenesis of post-traumatic stress disorder (PTSD) by determining the platelet 5-HT concentrations in Li and Han patients with PTSD in Hainan Province, China. Li and Han control groups of the same sample size have no statistical differences in gender and age distribution compared to those in the PTSD groups who were also examined. The platelet 5-HT concentrations were determined by high-performance liquid chromatography. In addition, the patients and controls were evaluated by the impact of event scale-revised (IES-R). IES-R showed that the total and sub-scale scores of three factors (avoidance, intrusion, and hyperarousal) of Li patients with PTSD were significantly higher than those of Han patients with PTSD. Scores of both PTSD groups were higher than those of their respective control groups. The platelet 5-HT concentration of the Li patients with PTSD (120.56 ± 118.05 ng/10(9) platelets) was lower than that of the Han patients with PTSD (271.43 ± 181.66 ng/10(9) platelets) and that of both Li and Han control groups (338.54 ± 156.46, 350.58 ± 169.19 ng/10(9) platelets, respectively). Differences existed in symptoms of PTSD in terms of avoidance, intrusion, and hyperarousal in the Li and Han patients with PTSD. The diminished 5-HT activity in patients with PTSD may be relevant to biochemical changes in the brain and body. The differences in these factors between ethnic groups could be due to their customs, social status, and culture.