title: High-affinity neurotensin binding sites in differentiated neuroblastoma N1E115 cells.
abstract: This paper describes the interaction of neurotensin with mouse neuroblastoma N1E115 cells. Neurotensin binding sites are undetectable in nondifferentiated neuroblastoma cells. They appear during cell differentiation in the presence of a low serum concentration and dimethyl sulfoxide, and reach a maximal level after 50-60 h of incubation under these conditions. The binding of monoiodo[Trp11]neurotensin to homogenates of differentiated N1E115 cells is specific, saturable, and reversible. The interaction is characterized by a dissociation constant of 150 pM and a maximal binding capacity of 9 fmol/mg of protein at 0 degrees C, pH 7.5. These binding parameters, as well as the specificity toward a series of neurotensin analogues, are similar for neurotensin receptors in N1E115 cells and for the high-affinity binding sites that had been previously characterized in rat brain synaptic membranes by means of the same radiolabeled ligand. The presence of high-affinity binding sites for neurotensin in the neuroblastoma N1E115 provides a useful model to study the cellular responses that are generated by the association of neurotensin to its receptor in electrically excitable cells.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002454:Cell Differentiation; D002460:Cell Line; D008433:Mathematics; D051379:Mice; D009447:Neuroblastoma / Q000378:metabolism*; D009496:Neurotensin / Q000031:analogs & derivatives / Q000378:metabolism*; D013997:Time Factors
chemical_list: D009496:Neurotensin; C039886:neurotensin, iodo-Tyr(11)-