Elevated platelet vesicular monoamine transporter density in untreated patients diagnosed with major depression

Autor: Abraham Weizman, Alex Aviv, Assaf Shelef, Michal Zucker, Moshe Rehavi
Rok vydání: 2002
Předmět:
Zdroj: Psychiatry Research. 112:251-256
ISSN: 0165-1781
Popis: The intraneuronal uptake of monoamines into brain synaptic vesicles is mediated by the vesicular monoamine transporter (VMAT2). This transporter plays a major role in monoamine storage and quantal release. Recently we demonstrated a high degree of similarity between the pharmacodynamic characteristics of platelet and brain VMAT2. In the present study we measured the VMAT2 density, using [3H]dihydrotetrabenazine ([3H]TBZOH) as a ligand, in platelets of untreated patients diagnosed with major depressive disorder (MDD) (n=10; three with recurrent depression and seven with first episode depression) compared to sex- and age-matched healthy control subjects (n=23). A significant elevation in the VMAT2 density (B(max)) was observed in the platelets of untreated MDD patients (+24%) compared to healthy control subjects. No significant change was found in the affinity constant (K(d)). The increased platelet VMAT2 density may reflect depression-related enhancement of the capacity to accumulate monoamines in the vesicles in the presence of lower monoamine turnover.
Databáze: OpenAIRE