Rimonabant effects on anxiety induced by simulated public speaking in healthy humans: a preliminary report

Abstract

Objective: We investigated the hypothesis that rimonabant, a cannabinoid antagonist/inverse agonist, would increase anxiety in healthy subjects during a simulation of the public speaking test.

Methods: Participants were randomly allocated to receive oral placebo or 90 mg rimonabant in a double-blind design. Subjective effects were measured by Visual Analogue Mood Scale. Physiological parameters, namely arterial blood pressure and heart rate, also were monitored.

Results: Twelve participants received oral placebo and 12 received 90 mg rimonabant. Rimonabant increased self-reported anxiety levels during the anticipatory speech and performance phase compared with placebo. Interestingly, rimonabant did not modulate anxiety prestress and was not associated with sedation, cognitive impairment, discomfort, or blood pressure changes.

Conclusions: Cannabinoid-1 antagonism magnifies the responses to an anxiogenic stimulus without interfering with the prestress phase. These data suggest that the endocannabinoid system may work on-demand to counteract the consequences of anxiogenic stimuli in healthy humans.

Keywords: CB1 receptor; SR141716; anxiety; public speaking test; rimonabant.

Figure 1

Changes in Visual Analogue Mood Scale factors induced by simulation of the public speaking test. B, baseline; P, prestress; A, anticipatory speech; S, speech performance; F1, poststress 1; and F2, poststress 2. Points indicate mean and vertical bars indicate standard error of the mean. *Indicates significant differences from placebo group (p < 0.05)

Figure 2

Changes in heart rate, systolic, and diastolic pressure induced by simulation of public speaking test. B, baseline; P, prestress; A, anticipatory speech; S, speech performance; F1, poststress 1; and F2, poststress 2. Points indicate mean and vertical bars indicate standard error of the mean