Correlation between increased urinary serotonin levels and coronary artery disease in cigarette smoking patients

Aim: Platelets secrete serotonin (5-hydroxytryptamine), which has several effects on the vascular wall and promotes thrombogenesis, mitogenesis, and the proliferation of smooth muscle cells. We therefore measured excreted levels of 5-hydroxytryptamine (5-HT) concentrations in urine as a means of assessing vascular lesions in patients with coronary artery disease ( CAD). Materials and methods: Subjects who underwent coronary angiography were classified into 2 groups according to their diagnosis. The CAD group consisted of 33 patients with coronary artery stenosis, whereas the healthy control group consisted of 30 subjects. An isocratic high-performance liquid chromatographic (HPLC) system with an electrochemical detector was used for the HPLC analysis of serotonin in urine. Results: The mean urine 5-HT concentration was significantly (P 0.01) higher in CAD patients than in the healthy control patients. Interestingly, the excretion of the urinary 5-HT levels in CAD patients were positively associated with cigarette smoking (r = 0.411, P 0.01), serum hs-CRP levels (r = 0.198, P 0.05), and age (r = 0.132, P 0.05).Conclusion: The increase in the amount of serotonin in urine in correlation with cigarette smoking, age, and hs-CRP may be important for future treatment strategies.