title: Brain synaptosomes harbor more than one cytoplasmic system of protein synthesis.
abstract: Synaptosomal protein synthesis from rat brain is selectively increased by learning and is massively enhanced during the recovery period from brain ischemia. To lay the groundwork for identification of the involved synaptic elements, we examined the effects induced by varying the concentrations of extracellular cations and endogenous calcium. Most of the recorded rate response curves exhibited biphasic profiles that suggested the presence of more than one translation system. Because comparable profiles were obtained by fully inhibiting mitochondrial translation, the data indicated the involvement of cytoplasmic translation systems present in different synaptosomal classes. Their properties may be individually investigated by exploiting the partially inhibited conditions we have described. The identification of the synaptic elements from which they originated and their newly synthesized proteins will significantly expand our understanding of the synaptic contribution to brain plastic events.
authors: Department of Biology, University of Naples Federico II, Naples, Italy.
authors: Carolina
authors: C
authors: Cefaliello
authors: Maria
authors: M
authors: Eyman
authors: Dominique
authors: D
authors: Melck
authors: Rosanna
authors: R
authors: De Stefano
authors: Eugenia
authors: E
authors: Ferrara
authors: Marianna
authors: M
authors: Crispino
authors: Antonio
authors: A
authors: Giuditta
mesh_terms: D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D061207:Calcium Ionophores / Q000494:pharmacology; D002412:Cations / Q000494:pharmacology; D002540:Cerebral Cortex / Q000648:ultrastructure*; D002614:Chelating Agents / Q000494:pharmacology; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism*; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D008715:Methionine / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013449:Sulfonamides / Q000494:pharmacology; D013460:Sulfur Isotopes / Q000378:metabolism; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
chemical_list: D061207:Calcium Ionophores; D002412:Cations; D002614:Chelating Agents; D004791:Enzyme Inhibitors; D009419:Nerve Tissue Proteins; D013449:Sulfonamides; D013460:Sulfur Isotopes; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D000001:Calcimycin; D004533:Egtazic Acid; C017967:W 7; D008715:Methionine; D002118:Calcium
keywords: brain plasticity; protein synthesis; synaptic elements; synaptosomes