Platelet α2-Adrenergic Receptors in Depression

Abstract
In recent years, the use of peripheral tissues to study possible neurochemical abnormalities in neuropsychiatric disorders has developed into a popular research strategy. Peripheral tissues, including platelets, lymphocytes, erythrocytes, and fibroblasts, have many biochemical parameters of interest to the neurobiologist, and their accessibility makes them particularly attractive for clinical studies. Because they have a number of biochemical features that closely resemble those of neurons, platelets have been the most extensively studied peripheral tissue in neuropsychiatric research. In fact, Pearse1has proposed that platelets, which along with other neuroendocrine tissues, form the APUD system (amineprecursoruptake anddecarboxylation system), are actually part of the nervous system. At the very least, many of the mediators of platelet function are known to be neurotransmitter substances that have also been shown to have important functions in various aspects of neuronal communication. In this issue, Garcia Sevilla et al2