RITANSERIN FACILITATES ANXIETY IN A SIMULATED PUBLIC-SPEAKING PARADIGM

The effects of ritanserin, a 5.HT2A/2C (5-hydroxytryptamine) antagonis t, have been investigated in simulated public speaking with healthy vo lunteers. The aim was to investigate the role of 5-HT in subjective ex perimental anxiety. There were three experimental groups each comprisi ng four or five males and 11 females. Subjects received placebo, ritan serin 2.5 or 10 mg, p.o. They rated themselves using the Spielberger S tate-Trait Anxiety Inventory and visual analogue scales factored into anxiety, sedation and discontentment scores. Autonomic measures includ ed skin conductance and heart rate. Subjects were told, 75 min after d rug or placebo ingestion, without prior warning, to prepare a 4-min sp eech. Measures were taken before, during and after the speech. Ritanse rin prolonged the anxiety induced by the procedure on the subjective r atings but had minimal effect on autonomic responses to the procedure. The result contrasts with an anxiolytic-like effect of ritanserin on aversively conditioned autonomic responses. The present finding is com patible with animal behavioural evidence that 5-HT has distinct and op posing roles in modulating conditioned and unconditioned anxiety.