Abstract
Cerebrospinal fluid (CSF) was collected from two patients with periodic ACTH and antidiuretic hormone (ADH) discharge syndrome, both during attacks and during attack-free periods. The concentration of neurotransmitter metabolites was measured by the high performance liquid chromatographic (HPLC) method with electrochemical detection, and compared with metabolite concentrations in CSF from normal controls. The levels of CSF 5-hydroxyidoleacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) were found to be increased during attacks in both patients, compared to control levels. In contrast, the levels of CSF homovanillic acid (HVA) decreased during attacks in both patients. During attack-free periods, the levels of CSF 5-HIAA, MHPG, and HVA did not differ from control level. These results suggest that there is increased activity of the serotonergic system in this syndrome. A relation between the attacks and the activity of the serotonergic system is further suggested by the observation that attacks were reduced or eliminated in these patients by the administration of granisetron hydrochloride. The possibility that the elimination of attacks by this drug is related to decreased serotonergic activity is discussed.
