Detecting Serotonin System in Rats with Myocardial Infarction and/or Depression after Selective Serotonin Reuptake Inhibitor Therapy

Objectives: The aim of this study is to explore the effects on serotonergic system of sertraline in the Sprague–Dawley (SD) rats of myocardial infarction (MI), depression, and depression post-MI. Methods: A total of 80 SD rats were randomly allocated into two pretreatment groups, including saline-pretreated group and sertraline-pretreated group. The sertraline-pretreated rats received sertraline and the saline-pretreated rats received saline for the past 4 weeks. Then, the two groups were randomly divided into four subgroups, respectively, including sham, MI, depression, and depression post-MI (MI + depression) subgroup. All animals were then sacrificed after 3 days to observe the effects of sertraline on levels of 5-HT, 5-HT 2A R, and SERT in the rat serum, platelet, and brain. Results: As compared with saline treatment group, serum 5-HT decreased significantly in sham subgroup and increase significantly in MI, depression, and MI-depression subgroups, platelet 5-HT increased significantly, brain 5-HT decreased significantly in the four subgroups after sertraline treatment (all P < 0.05). As compared with saline treatment group, platelet 5-HT 2A R decreased significantly in the sham subgroup and increased significantly in MI and depression subgroups, brain 5-HT 2A R increased significantly in MI subgroup and decreased significantly in depression and MI + depression subgroups after sertraline treatment (all P < 0.05). As compared with saline treatment group, serum SERT decreased significantly in the sham subgroup and increased significantly in depression subgroup, platelet SERT decreased significantly in the four subgroups and brain SERT increased significantly in sham and depression subgroups and decrease significantly in MI subgroup after sertraline treatment (all P < 0.05). Conclusion: Sertraline regulated 5-HT concentration of peripheral blood and brain according to 5-HT 2A R and SERT, thereby regulating the platelet function in various pathological states including MI, depression, and depression post-MI.