Tryptophan and serotonin in blood and platelets of depressed patients: Effect of an antidepressant treatment
Por:
Moreno J., Campos M.G., Lara C., López G., Pavón L., Hernández Ma.E., Sentíes H., González-Olvera J., Torruco M., Arango I., Heinze G., Torner C.
Publicada:
1 ene 2006
Resumen:
Platelets have serotonin (5-HT) uptake and storage mechanisms similar to those from neurons. In addition, they represent nearly 99% of blood 5-HT concentration. For these characteristics, platelets are considered useful biomarkers of the serotonergic synaptic neurotransmission, particularly in psychiatric disturbances such as depression. However, most studies which have evaluated platelet 5-HT concentrations in depression have not shown similar findings. It has been suggested that changes in plasma tryptophan (TRP) concentrations might modify 5-HT concentration in the brain, as well as in platelets. Likewise, decreased plasma concentrations of TRP have been found in depressed patients, and the selective 5-HT reuptake inhibitors (SSRIs) induce changes in platelet 5-HT concentration. Considering the controversy surrounding platelet 5-HT concentrations in depressed patients, and the fact that blood 5-HT and TRP have not been studied in the Mexican population, we decided to study 5-HT and tryptophan concentrations in blood and platelets from depressed and control Mexican subjects to evaluate a possible correlation with the severity of depression. The effect of fluoxetine and citalopram treatment on blood and platelet 5-HT and TRP concentrations in depressed patients was also studied. Material and methods: Depressed patients - The patients of this study were carefully selected and evaluated. Scales based on semi-structured interviews were applied (MINI and SCID-II) by clinical investigators to reduce any possible bias in patient selection. The influence of the seasonal variability on the 5-HT or TRP blood concentrations was controlled by pairing depressed patients and healthy subjects according to age, gender and, in the case of women, menstrual cycle phase. Patients with a complete remission of depression symptoms (defined as a score not higher than 5 points in the Hamilton's scale, and lower than 7 points in Beck's scale) were asked for a blood sample to measure platelet and blood concentrations of 5-HT and TRP. The patients were weighted before the treatment and after their improve-ment. Control subjects: The control group was integrated by 30 healthy subjects, 24 women and 6 men, with an average age of 32.3 ± 10.8 years. Participants were recruited from the overall Mexican population, int
Filiaciones:
Moreno J.:
División de Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Centro Médico La Raza, Instituto Mexicano del Seguro Social, México D.F., Mexico
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Laboratorio Clínico, Instituto Nacional de Psiquiatría Ramón de la Fuente, Calzada México-Xochimilco 101, 14370, Mexico DF, Mexico
Campos M.G.:
Unidad de Investigación Médica en Farmacología, Hospital de Especialidades, Instituto Mexicano del Seguro Social, México, D.F., Mexico
Lara C.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, Mexico
López G.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Pavón L.:
Dirección de Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Hernández Ma.E.:
Dirección de Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Sentíes H.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
González-Olvera J.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Torruco M.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Arango I.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Heinze G.:
Servicios Clínicos, Instituto Nacional de Psiquiatría Ramón de la Fuente, México D.F., Mexico
Torner C.:
Departamento de Atención a la Salud, CBS, Universidad Autónoma Metropolitana-Xochimilco, México D.F., Mexico
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