Neurotensin and its analogs--correlation of specific binding with stimulation of cyclic GMP formation in neuroblastoma clone N1E-115.
The receptors which mediate neurotensin-stimulated intracellular cyclic GMP formation in murine neuroblastoma clone N1E-115 [J. A. Gilbert and E. Richelson, Eur. J. Pharmac. 99, 245 (1984)] were further characterized. The binding of [3H]neurotensin to intact N1E-115 cells at 0 degree displayed specificity, saturability, reversibility, and tissue linearity. A single class of neurotensin receptors was demonstrated with an apparent KD of 9-11 nM and a Bmax of 180-250 fmoles/10(6) cells, determined by the type of serum employed in the cellular culture medium. A number of neurotensin analogs and fragments were compared for their ability to inhibit [3H]neurotensin binding and stimulate intracellular cyclic GMP formation with intact N1E-115 cells. A direct correlation was found to exist between the KD and EC50 for each peptide. The carboxyl-terminal portion of neurotensin proved to be responsible for the binding and biochemical activities of this peptide with clone N1E-115. Neurotensin(8-13) was, in fact, fifty times more potent than native neurotensin in stimulating intracellular cyclic GMP formation and had an 18-fold higher affinity for the neurotensin receptor on this neuronal cell type.
Gilbert
J A
JA
Moses
C J
CJ
Pfenning
M A
MA
Richelson
E
E
D000818:Animals; D001667:Binding, Competitive; D002460:Cell Line; D006152:Cyclic GMP / Q000096:biosynthesis*; D006162:Guanylate Cyclase / Q000378:metabolism; D051379:Mice; D009447:Neuroblastoma / Q000378:metabolism*; D009496:Neurotensin / Q000031:analogs & derivatives / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D011869:Radioligand Assay; D018028:Receptors, Neurotensin; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D013329:Structure-Activity Relationship
D010446:Peptide Fragments; D018028:Receptors, Neurotensin; D017981:Receptors, Neurotransmitter; D009496:Neurotensin; D006162:Guanylate Cyclase; D006152:Cyclic GMP