Drug Discrimination Studies in Animals

Abstract

Although not without controversy,¹ animal models of human pathology have been used to study a wide range of issues^2-10 (Table I). The analogy from the animal model to the human condition can take a variety of forms and can provide different types of information. Ideally, such models would accurately simulate the human syndrome, which they are purported to represent in such a way that they fulfill the requisite characteristics for animal models proposed by Robbins and Sahakian.¹¹ Briefly, they suggest that animal models should (1) mimic the behavioral features of the disorder, (2) have a similar etiology, and (3) show recovery in behavioral features in response to treatments that alleviate symptoms in humans. Although such criteria may represent the exemplar of an animal model, many useful models may not meet each of these requirements. For example, Kometsky¹² described a continuum of levels at which animal models might represent a human problem of interest. In his analysis, models are seen as homologous if there is a correspondence in the etiology of the disease and the model. At another level, models may be only isomorphic. That is, while there are similarities between the model and the human state, the cause of the condition created for the model may be different from the cause in humans. Finally, the model may not have a direct resemblance to the disease but may be a nonhomologous, nonisomorphic representation that has some predictive value concerning some aspect of the disease.