alpha-Conotoxin imperialis I inhibits nicotine-evoked hormone release and cell proliferation in human neuroendocrine carcinoma cells.
alpha-Conotoxins are small peptides present in the venom of different species of marine snails of the Conus genus that target nicotinic acetylcholine receptors (nAChRs), with a marked specificity for muscle-type nAChRs. alpha-Conotoxin Imperialis I (alpha-Ctx-Iml), from Conus imperialis, has been recently described as a potent antagonist of mammalian neuronal alpha-bungarotoxin (alpha-Bgtx)-sensitive nAChRs. Human small cell lung carcinoma (SCLC) is a very aggressive tumor composed of neuroendocrine secretory cells. We demonstrated that human SCLC cells express neuronal-type alpha-Bgtx-sensitive nAChRs, and that their activation causes secretion of mitogenic hormones and stimulates cell proliferation, alpha-Ctx ImI inhibits both these nicotinic effects, and could therefore be considered a new important tool for investigating human neuronal-type alpha-Bgtx-sensitive nAChRs.
Codignola
A
A
CNR Center of Cellular and Molecular Pharmacology, University of Milan, Italy.
McIntosh
J M
JM
Cattaneo
M G
MG
Vicentini
L M
LM
Clementi
F
F
Sher
E
E
D018288:Carcinoma, Small Cell / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D020916:Conotoxins; D006728:Hormones / Q000378:metabolism*; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D009538:Nicotine / Q000494:pharmacology; D018722:Nicotinic Agonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D011978:Receptors, Nicotinic / Q000187:drug effects; D014407:Tumor Cells, Cultured
D020916:Conotoxins; D006728:Hormones; D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D009842:Oligopeptides; D011978:Receptors, Nicotinic; C087686:alpha-conotoxin ImI; D009538:Nicotine