Biomaterial Database

Differential regulation of two molecular forms of a mu-opioid receptor type by sodium ions, manganese ions and by guanyl-5'-yl imidodiphosphate. 1986

P Jauzac, and B Frances, and A Puget, and C Moisand, and J C Meunier

The rabbit cerebellum contains a very high proportion (up to 80%) of mu-opioid receptor sites (Meunier, J.C., Kouakou, Y., Puget, A. and Moisand, C., Mol. Pharmacol. 24, 23-29, 1983). A membrane fraction derived therefrom is labeled either with the opioid agonist, 3H-etorphine or with the opioid antagonist, 3H-diprenorphine, and solubilized with digitonin. Centrifugation of the soluble extracts in linear sucrose gradients reveals that bound 3H-etorphine sediments faster than does bound 3H-diprenorphine: 12S vs 10S. Pre-incubation of membranes and radioligand in the presence of 120 mM NaCl results in considerably decreased recovery of the 3H-agonist in 12S form while recovery of the 3H-antagonist in 10S form is substantially increased. The opposite situation is observed when the membranes have been prelabeled with radioligand in the presence of 1 mM MnCl2. Guanyl-5'-yl imidodiphosphate, a metabolically stable structural analog of GTP is found to selectively reduce recovery of labeled 12S receptors while it does not affect that of labeled 10S receptors. These data indicate that the mu-opioid receptor from rabbit cerebellum is capable of existing in two forms which differ in apparent molecular size: an "antagonist" (10S) form of apparent Mr approximately 230,000 which is stabilized in the presence of sodium ions and an "agonist" (12S) form of apparent Mr approximately 300,000 which, unlike the antagonist one, is sensitive to guanyl-5'-yl imidodiphosphate. It is thought that the form of larger apparent size represents the mu-opioid receptor associated with a guanine nucleotide regulatory protein.

UI	MeSH Term	Description	Entries
D008345	Manganese	A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
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
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D002531	Cerebellum	The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.	Cerebella,Corpus Cerebelli,Parencephalon,Cerebellums,Parencephalons
D004174	Diprenorphine	A narcotic antagonist similar in action to NALOXONE. It is used to remobilize animals after ETORPHINE neuroleptanalgesia and is considered a specific antagonist to etorphine.	Diprenorphine Hydrochloride,Revivon,Hydrochloride, Diprenorphine
D004336	Drug Antagonism	Phenomena and pharmaceutics of compounds that inhibit the function of agonists (DRUG AGONISM) and inverse agonists (DRUG INVERSE AGONISM) for a specific receptor. On their own, antagonists produce no effect by themselves to a receptor, and are said to have neither intrinsic activity nor efficacy.	Antagonism, Drug,Antagonisms, Drug,Drug Antagonisms
D005048	Etorphine	A narcotic analgesic morphinan used as a sedative in veterinary practice.	Ethorphine,M99