In this review the naturally occurring β-carbolines norharman and harman in human beings and mammals will be discussed. These β-carbolines have been recognized as aromatic alkaloids, which can be detected in very low concentrations in human plasma. Norharman and especially harman display moderate affinity to the benzodiazepine receptor. The biosynthesis of these compounds in vivo, the localization, the biological effects and the probable involvement of these compounds in the cause of psychopathologic states will be discussed. This with a special focus on alcoholism, heroin addiction, psychosis and anxiety disorders. In some of these clinical pictures the concentration of norharman is increased. Whether this is a causality or a matter of minor importance is still unknown.

We studied the effects of pentagastrin, an analogue of the cholecystokinin tetrapeptide (CCK4), in 15 patients with panic disorder and 15 healthy controls. Three different intravenous dosages of pentagastrin (0.1, 0.3 and 0.6 μ/kg) and placebo (saline) were investigated. Subjects were randomly allocated to two of the four dosage groups and tested on two separate occasions, one week apart, using a double-blind incomplete block design. A total of 59 intravenous injections were carried out. The panic rate with pentagastrin, irrespective of the dosage, was 55% (12/22) for patients and 5% (1/22) for controls. None of the subjects panicked with saline. The frequency of panic attacks between the three pentagastrin doses in patients was not different. One control subject had a panic-like attack at the highest dose of pentagastrin. These findings concur with previous studies on the panicogenic effect of CCK4 and pentagastrin and suggest a greater sensitivity for CCK agonists in patients suffering from panic disorder than in healthy controls.

In this review article four neuropeptides: adrenocorticotrope hormone (ACTH), corticotrope releasing hormone (CRH), neuropeptide- Y(NPY) and cholecystokinin (CCK) are discussed with respect to their possible role in the pathogenesis of anxiety disorders. First the presumable working mechanism of these peptides in the brain is mentioned. In addition, the relationship of these peptides and anxiety is outlined using neuroanatomical and electrophysiological research data. Subsequently, animal experiments and human research findings are discussed. Most of the research findings so far are obtained from animal data. Only with respect to CCK, there is increasing evidence, also from human studies, that this peptide might play a role in the pathogenesis of anxiety disorders. The putative role of the other peptides remains to be estab lished in future research.