ABSTRACT
Endogenous opioids and exogenously administered delta opioid receptor agonists have been demonstrated to have antidepressant-like effects in animal models used to evaluate novel antidepressant compounds. This chapter reviews some of the previous research investigating the role of the opioid system, and more specifically the delta opioid receptor system, in clinical depression and in animal models used to study human depression and antidepressant treatments. In addition, this chapter discusses the interpretation of animal models of depression and their uses in the evaluation of new potential therapeutics.
