Neurotensin elevates cytosolic calcium in small cell lung cancer cells.
The ability of neurotensin (NT) to elevate cytosolic Ca2+ in small cell lung cancer (SCLC) cells was investigated using the fluorescent Ca2+ indicator Fura 2-AM. Using SCLC cell line NCI-H345, NT elevated cytosolic Ca2+ levels in a concentration-dependent manner. Using a 10 nM dose, NT and C-terminal fragments such as NT(8-13) but not N-terminal fragments such as NT(1-8) elevated the cytosolic Ca2+ levels. Because EGTA (5 mM) did not affect the NT response, NT may cause release of Ca2+ from intracellular stores. These data indicate that SCLC NT receptors may use Ca2+ as a second messenger.
Staley
J
J
Department of Biochemistry, George Washington University School of Medicine and Health Sciences, Washington, DC 20037.
Fiskum
G
G
Davis
T P
TP
Moody
T W
TW
D002118:Calcium / Q000378:metabolism*; D018288:Carcinoma, Small Cell / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism*; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D009496:Neurotensin / Q000031:analogs & derivatives / Q000502:physiology*; D015290:Second Messenger Systems / Q000502:physiology; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
D009496:Neurotensin; D002118:Calcium