Screening of Antianxiety Drugs

Introduction & rationale

• Definition — Anxiolytic (antianxiety) screening is the experimental in-vitro + in-vivo evaluation of candidate compounds for the ability to reduce experimentally-induced or spontaneously-expressed anxiety-like behaviour in laboratory animals before clinical development.
• Why a battery, not one test — Human pathological anxiety (interference with function, somatic and emotional manifestations, reduced productivity) is too complex for any single animal model to reproduce — so no single test suffices; a battery establishing a spectrum of activity is required for predictive value.
• Bidirectional paradigms — The same tests detect both anxiolytic (↑ open-arm exploration, ↑ punished responding) and anxiogenic activity (the opposite), since the paradigms are bidirectional.
• Four assay classes — Assays group as (a) in-vitro receptor-binding screens, (b) unconditioned ethological (exploration–conflict) tests, (c) conditioned operant conflict/punishment tests, and (d) physiological / endocrine readouts.