A probable neurobiological role for the trace amines began to emerge as soon as techniques sufficiently sophisticated to detect them were developed. Techniques for quantitative analyses included radioenzymatic procedures and, more recently, HPlC-EC and auto mated GC-MS. The methods are applied after separation of the sub stances to be analyzed and after their purification by physicochemical procedures that are becoming more and more efficient. The identification and quantitative analysis of minute amounts of trace amines in biological fluids or tissues is in itself a remarkable technological...