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Part IX. Opiate Receptors and the Behavioral Implications of Endorphins: OPIATE RECEPTORS AND OPIOID PEPTIDES: AN OVERVIEW

It is my assignment to present an overview of the area of opiate receptors and opioid peptides. This is a not inconsiderable challenge, in terms of both the selection of topics to fit into the allotted space and the level of previous knowledge of the field to be expected of my audience. After reflection I have decided to review as concisely as possible the physiology and distribution of opiate receptors and of opioid peptides. I then plan to concentrate on two areas that have received considerable attention recently. One is the question of the existence of more than one type of opiate receptor; the other is the evidence for possible functions of the endogenous opioid system and, in particular, those aspects of endorphin distribution and actions that have given rise to the hypothesis of their possible involvement in mental disease.