Opioid-Mediated Control of Neuroendocrine Function

Abstract

The purpose of this chapter is to discuss the historical perspectives, current state of the literature, and suggested new strategies for the identification of the opioid receptors involved in the control of neuroendocrine function. As will become apparent, there is a vast body of data on the neuroendocrine effects of various opiate agonists and antagonists, and the involvement of endogenous opioid peptides (EOPs*) in neuroendocrine function, but an extensive literature review suggests that we know only one factor for certain: Exogenous and endogenous opioids exert pronounced effects on endocrine function, and EOPs may be intimately involved in the physiological regulation of endocrine function. However, we cannot definitively draw conclusions as to which EOPs are involved in these effects or the opioid receptor subtype that mediates these effects. The reasons for this conclusion will be discussed fully below, but it seems clear that, after intense study for nearly two decades, we can only conclude that compounds with some selectivity for x and.t receptors influence neuroendocrine function. Also, we are still uncertain whether one or both receptors are involved