UNIT 5.18 Models of Anxiety: Ultrasonic Vocalizations of Isolated Rat Pups

  1. Lucianne Groenink1,
  2. P. Monika Verdouw1,
  3. Ruud van Oorschot1,
  4. Berend Olivier1,2,3

Published Online: 1 DEC 2008

DOI: 10.1002/0471141755.ph0518s43

Current Protocols in Pharmacology

Current Protocols in Pharmacology

How to Cite

Groenink, L., Verdouw, P. M., van Oorschot, R. and Olivier, B. 2008. Models of Anxiety: Ultrasonic Vocalizations of Isolated Rat Pups. Current Protocols in Pharmacology. 43:5.18:5.18.1–5.18.14.

Author Information

  1. 1

    Psychopharmacology, Department of Pharmaceutical Sciences, Utrecht Institute for Pharmaceutical Sciences and Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands

  2. 2

    PsychoGenics Inc., Tarrytown, New York

  3. 3

    Deptartment of Psychiatry, Yale University School of Medicine, New Haven, Connecticut

Publication History

  1. Published Online: 1 DEC 2008
  2. Published Print: DEC 2008


Described in this unit is the ultrasonic distress vocalization test in rat pups. This test is a reliable method for detecting anxiolytic properties of test compounds. In this test, ultrasonic vocalizations (30 to 50 kHz) are elicited by separating rat pups of 9 to 11 days of age from their mother and littermates for a brief period of time. The test can be performed under two different stress conditions. Pups are placed in isolation in either a warm (37°C) or cold (18°C) environment for 5 min. The total number and duration of ultrasonic calls emitted by the pups during this period is used as an index of anxiety. Established anxiolytic compounds, including benzodiazepines, serotonin1A receptor agonists, and selective serotonin reuptake inhibitors (SSRIs), consistently reduce the number and cumulative duration of these ultrasonic distress vocalizations. Curr. Protoc. Pharmacol. 43:5.18.1-5.18.14. © 2008 by John Wiley & Sons, Inc.


  • anxiety;
  • ultrasonic vocalization;
  • distress;
  • rat pup;
  • negative geotaxis