Biomaterial Database

Opiate receptors: an introduction. 1987

J J Carmody

Current status of opiate receptors and their agonists is reviewed--basic aspects of receptor theory, the importance of stereospecificity in drug-receptor interactions and the role of 'second messengers' in drug action. The three classes of endogenous opioids, originating from three distinct genes, are discussed: pro-opiomelanocortin, giving rise to beta-endorphin, ACTH and various MSHs; pro-enkephalin, giving methionine enkephalin and leucine enkephalin; and prodynorphin; their anatomical distribution and the main classes of receptors with which they interact, the mu-receptor, with a high affinity for met-enkephalin and beta-endorphin (as well as morphine and dynorphin A); the delta-receptor for which the primary ligand is leu-enkephalin; and the kappa-receptor which is the main target for the dynorphins. Functional roles for endogenous opioids are considered. Essentially they are inhibitory to target neurones, depressing motor reflexes, baroreflexes and nociception. They also have roles in the response to physical and psychological stress.

UI	MeSH Term	Description	Entries
D011957	Receptors, Opioid	Cell membrane proteins that bind opioids and trigger intracellular changes which influence the behavior of cells. The endogenous ligands for opioid receptors in mammals include three families of peptides, the enkephalins, endorphins, and dynorphins. The receptor classes include mu, delta, and kappa receptors. Sigma receptors bind several psychoactive substances, including certain opioids, but their endogenous ligands are not known.	Endorphin Receptors,Enkephalin Receptors,Narcotic Receptors,Opioid Receptors,Receptors, Endorphin,Receptors, Enkephalin,Receptors, Narcotic,Receptors, Opiate,Endorphin Receptor,Enkephalin Receptor,Normorphine Receptors,Opiate Receptor,Opiate Receptors,Opioid Receptor,Receptors, Normorphine,Receptors, beta-Endorphin,beta-Endorphin Receptor,Receptor, Endorphin,Receptor, Enkephalin,Receptor, Opiate,Receptor, Opioid,Receptor, beta-Endorphin,Receptors, beta Endorphin,beta Endorphin Receptor,beta-Endorphin Receptors
D004723	Endorphins	One of the three major groups of endogenous opioid peptides. They are large peptides derived from the PRO-OPIOMELANOCORTIN precursor. The known members of this group are alpha-, beta-, and gamma-endorphin. The term endorphin is also sometimes used to refer to all opioid peptides, but the narrower sense is used here; OPIOID PEPTIDES is used for the broader group.	Endorphin
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia