UCB 29120 belongs to a novel family of compounds possessing interesting behavioral and physiological properties. Behavioral studies in the rat have revealed the ability of the compound to inhibit scopolamine-induced amnesia while physiological studies demonstrated a significant drug-induced hypothermic response and increased corticosterone plasma levels following acute administration of the compound. In the present study we examined the time-course effects of acute administration of UCB 29120 on levels of catecholamines (norepinephrine, NE; dopamine, DA), indoleamines (serotonin, 5-HT) and metabolites (3,4-diydroxyphenylacetic acid, DOPAC; 5-hydroxyindoleacetic acid, 5-HIAA) in the rat hypothalamus. Hippocampal, septal and striatal tissue content of the same were also examined at the longest time point employed. In the hypothalamus, UCB 29120 induced significant decreases in NE content 30 min following administration which persisted for at least an additional 30 min, while significant increases in DA and/or DOPAC (and the DOPAC/DA ratio) were measured as early as 5 min following administration and persisted through at least a total of 120 min. Similar, significant changes in dopaminergic parameters were also evident in the other three brain regions at 120 min post-administration. No significant alterations in hypothalamic 5-HT or 5-HIAA were measured at any time point. Acute administration of UCB 29120 may selectively influence catecholaminergic neurotransmitter systems in rat brain.