Animal models and human depressive disorders.

Clinical depressive disorders are complex in presentation, dissimilar in origins and course, and often pleomorphic in character. An adequate understanding of their origins, biological substrates, and amenability to established and novel forms of therapy demands biological and social interventions which cannot always readily or ethically be carried out in a clinical setting. One useful complementary approach to clinical research utilizes preclinical models for laboratory investigations in parallel. The present paper reviews current approaches to modelling depression using animals, with particular emphasis upon phylogenetic constraints, systematic validity and reliability, and nosological limitations. Preclinical models are useful and necessary adjuncts for adequately understanding depression in humans. However, their utility remains a direct function of a continuing dialogue between clinical and laboratory research, and demands scrupulous observation and methodological rigor on the part of both clinicians and experimental researchers.