Biogenic Amines and Affective Disorders

Abstract

There is now a considerable amount of evidence suggesting that the biogenic amines are involved in the etiology of the affective disorders. This evidence consists of a growing number of investigations of the biogenic amines in patients suffering from depression and mania, and also of observations of the effect of manipulating brain amines on mood in patients and in normal subjects. This paper will examine some of the direct evidence for a disturbance in biogenic amines in patients suffering from affective disorders, to examine the etiological implications of these findings, and to consider what the implications of these findings are for treatment. I shall be dealing with the indoleamines—serotonin (5-hydroxytryptamine) and tryptamine—whose biosynthesis and metabolism are illustrated in Figure 1. I do this not because I naively think that only serotonin is important in these conditions, but because most of my own research interests have been centered in this area; in a later paper, Dr. Schildkraut will describe catecholamine metabolism in affective disorders. Moreover, I should like to stress my view that the clinical pathology of the affective disorders is probably very complex, involving not only the biogenic amines but probably other abnormalities as well.