Regulation of cyclic GMP levels by neurotensin in neuroblastoma clone N1E115.
The binding of 125I-labeled [monoiodo-Tyr3]neurotensin to intact neuroblastoma N1E115 cells and the effect of neurotensin on the intracellular concentration of cyclic nucleotides were studied at 37 degrees C and under physiological conditions of pH and ionic strength. The radiolabeled neurotensin analogue bound specifically to differentiated cells with a dissociation constant of 0.75 nM and a maximal binding capacity of 45 fmol/10(6) cells. Incubation of neuroblastoma cells with neurotensin in the presence of calcium ions resulted in a transient increase of 10 fold over basal level of the intracellular cyclic GMP concentration. Half-maximal stimulation was obtained with 2 nM neurotensin. Under identical conditions the cyclic AMP concentration only decreased by 20-30%. These results suggest that cyclic GMP is a second messenger of neurotensin in neuroblastoma clone N1E115.
Amar
S
S
Mazella
J
J
Checler
F
F
Kitabgi
P
P
Vincent
J P
JP
D000818:Animals; D001667:Binding, Competitive; D002999:Clone Cells / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D008433:Mathematics; D009447:Neuroblastoma / Q000378:metabolism*; D009496:Neurotensin / Q000031:analogs & derivatives / Q000494:pharmacology*; D018028:Receptors, Neurotensin; D017981:Receptors, Neurotransmitter / Q000378:metabolism; D013997:Time Factors
D018028:Receptors, Neurotensin; D017981:Receptors, Neurotransmitter; D009496:Neurotensin; D006152:Cyclic GMP