Bombesin-like peptides elevate cytosolic calcium in small cell lung cancer cells.
The ability of bombesin-like peptides to elevate intracellular Ca2+ levels in small cell lung cancer cells was investigated using the fluorescent Ca2+ indicator Fura 2. Nanomolar concentrations of bombesin elevated cytosolic Ca2+ levels in the absence or presence of extracellular Ca2+. Potent bombesin receptor agonists, such as gastrin releasing peptide (GRP) or (GRP)14-27 elevated cytosolic Ca2+ levels whereas inactive compounds such as (D-Trp8)bombesin or (GRP)1-16 did not. Furthermore, the bombesin receptor antagonist (D-Arg1, D-Pro2, D-Trp7,9, Leu11) substance P (30 microM) had no effect on the Ca2+ levels by itself but antagonized the increase in Ca2+ caused by 10 nM or 100 nM bombesin. These data suggest that bombesin receptors may regulate the release of Ca2+ from intracellular organelles in small cell lung cancer cells.
D001572:Benzofurans; D001839:Bombesin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D018288:Carcinoma, Small Cell / Q000503:physiopathology*; D002460:Cell Line; D003600:Cytosol / Q000378:metabolism; D016257:Fura-2; D019886:Gastrin-Releasing Peptide; D006801:Humans; D066298:In Vitro Techniques; D009842:Oligopeptides / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology; D018004:Receptors, Bombesin; D017981:Receptors, Neurotransmitter / Q000502:physiology*; D013004:Somatostatin / Q000494:pharmacology; D013329:Structure-Activity Relationship; D013373:Substance P / Q000037:antagonists & inhibitors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D001572:Benzofurans; D009842:Oligopeptides; D010455:Peptides; D018004:Receptors, Bombesin; D017981:Receptors, Neurotransmitter; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D013004:Somatostatin; D019886:Gastrin-Releasing Peptide; D001839:Bombesin; D002118:Calcium; D016257:Fura-2