[Serotonin metabolism in patients with brain tumors].

In patients with brain tumours there was revealed an increase in the content of serotonin, 5-oxyindol acetic acid (5-OAA) and melatonin in the liquor, and of serotonin in the plasma rich with platelets. The content of serotonin or products of its metabolism in the liquor, as well as of serotonin in platelets depends on the involvement of truncus cerebri and hypothalamus in the pathologic process and on the gravity of the patient's condition. The serotonin content, in contrast to 5-OAA, s significantly higher in patients with tumours attended by epileptic attacks. The data obtained testify to a possible role of serotonin in the pathogenetic mechanisms of tumours development in the central nervous system.