• Media type: E-Article
  • Title: Differential effects of the translocator protein 18 kDa (TSPO) ligand etifoxine and the benzodiazepine alprazolam on startle response to predictable threat in a NPU-threat task after acute and short-term treatment
  • Contributor: Brunner, Lisa-Marie; Maurer, Franziska; Weber, Kevin; Weigl, Johannes; Milenkovic, Vladimir M.; Rupprecht, Rainer; Nothdurfter, Caroline; Mühlberger, Andreas
  • Published: Springer Science and Business Media LLC, 2022
  • Published in: Psychopharmacology, 239 (2022) 7, Seite 2233-2244
  • Language: English
  • DOI: 10.1007/s00213-022-06111-x
  • ISSN: 1432-2072; 0033-3158
  • Origination:
  • Footnote:
  • Description: Abstract Rationale Benzodiazepines have been extensively investigated in experimental settings especially after single administration, which mostly revealed effects on unpredictable threat (U-threat) rather than predictable threat (P-threat). Given the need for pharmacological alternatives with a preferable side-effect profile and to better represent clinical conditions, research should cover also other anxiolytics and longer application times. Objectives The present study compared the acute and short-term effects of the translocator protein 18 kDa (TSPO) ligand etifoxine and the benzodiazepine alprazolam on P-threat and U-threat while controlling for sedation. Methods Sixty healthy male volunteers, aged between 18 and 55 years, were randomly assigned to receive a daily dose of either 150 mg etifoxine, 1.5 mg alprazolam, or placebo for 5 days. On days 1 and 5 of intake, they performed a NPU-threat task including neutral (N), predictable (P), and unpredictable (U) conditions, while startle responsivity and self-reports were studied. Sedative effects were assessed using a continuous performance test. Results Neither alprazolam nor etifoxine affected startle responsivity to U-threat on any of the testing days. While etifoxine reduced the startle response to P-threat on day 1 of treatment for transformed data, a contrary effect of alprazolam was found for raw values. No effects on self-reports and no evidence of sedation could be observed for either drug. Conclusions None of the anxiolytic substances had an impact on startle potentiation to U-threat even after several days of intake. The effects of the anxiolytics on startle responsivity to P-threat as well as implications for future studies are discussed.