The test retest model of anxiety: An appraisal of findings to explain benzodiazepine tolerance.

A test retest protocol in animal model of anxiety induces an increase of anxious behavior and a loss of benzodiazepine-induced effect. This effect, known as the "one trial tolerance", is mainly observed in the elevated plus maze, an ethological model of anxiety in mice, but also in the four plate test, a model based on punishment. A review of some hypotheses based on behavioral, pharmacological and neurochemical approaches are proposed here to explain this benzodiazepines tolerance phenomenon.