ABSTRACT
This book focuses on biological and pharmacological effects of ligands interacting with delta opioid receptors. Selective or even specific ligands for one type or subtype of the receptor are tools to separate and characterize the roles of particular receptors in the functions of living organism. Nevertheless, most if not all functions of endogenous opioids reflect their concerted action upon processes mediated by a multiplicity of opioid receptors. Therefore, it is not unexpected that endogenous opioid peptides express a broad spectrum of affinity to neuropeptide G protein-coupled receptors. The prospective development of new opioid drugs has taken into account such multitarget, coordinated action. This chapter surveys the biological effects resulting from biphalin, a compound with significant binding to the delta opioid receptor as well as to other types of opioid receptors.
