2 Opiate Receptors and Opioid Peptides: Are They Involved in Drug Addiction?

INTRODUCTION The recent discoveries of the existence of opiate receptors and of endogenous opioid peptides in the central nervous system of animals and man have raised hopes that an understanding of the molecular mechanism of drug addiction may soon be achieved. It is clear from the title of this chapter that that day is not yet here. I will give a brief chronological review of the significant discoveries and developments and will then summarize recent research that bears on the possible involvement of the endogenous opioid system in drug addiction. THE DISCOVERY OF OPIATE RECEPTORS