Human nicotinic receptors in chromaffin cells: characterization and pharmacology
- 258 Downloads
During the last 10 years, we have been working on human chromaffin cells obtained from the adrenal gland of organ donors that suffered encephalic or cardiac death. We first electrophysiologically characterized the nicotinic acetylcholine receptors (nAChRs) activated by acetylcholine, and their contribution to the exocytosis of chromaffin vesicles and release of catecholamines. We have shown that these cells possess an adrenergic phenotype. This phenotype may contribute to an increased expression of α7 nAChRs in these cells, allowing for recording of α7 nAChR currents, something that had previously not been achieved in non-human species. The use of α-conotoxins allowed us to characterize non-α7 nAChR subtypes and, together with molecular biology experiments, conclude that the predominant nAChR subtype in human chromaffin cells is α3β4* (asterisk indicates the posible presence of additional subunits). In addition, there is a minor population of αxβ2 nAChRs. Both α7 and non-α7 nAChR subtypes contribute to the exocytotic process. Exocytosis mediated by nAChRs could be as large in magnitude as that elicited by calcium entry through voltage-dependent calcium channels. Finally, we have also investigated the effect of nAChR-targeted tobacco cessation drugs on catecholamine release in chromaffin cells. We have concluded that at therapeutic concentrations, varenicline alone does not increase the frequency of action potentials evoked by ACh. However, varenicline in the presence of nicotine does increase this frequency, and thus, in the presence of both drugs, the probability of increased catecholamine release in human chromaffin cells is high.
KeywordsHuman Chromaffin cells Nicotinic receptors α-conotoxins Varenicline Nicotine Patch-clamp
This review is devoted to Prof. Antonio García, for his fervor and dedication to scientific research. And all anonymous organ donors and their families, for their generosity and collaboration in our scientific work.
This work was supported by grants from the Spanish Government (BFU2005-00743, BFU2008-01382/BFI, BFU2011-27690 to A.A.), the Spanish Ministerio de Economía, Industria y Competitividad (BFU2012-30997 and BFU2015-69092 to A.A.), the European Research Agency (NRHACC-329956 to A.A.), and the US National Institutes of Health (GM48677 and GM103801 to J.M.M).
- 4.Azam L, Maskos U, Changeux JP, Dowell CD, Christensen S, De Biasi M, McIntosh JM (2010) α-Conotoxin BuIA[T5A;P6O]: a novel ligand that discriminates between α6ß4 and α6ß2 nicotinic acetylcholine receptors and blocks nicotine-stimulated norepinephrine release. FASEB J 24:5113–5123Google Scholar
- 7.Campos-Caro A, Smillie FI, Dominguez del Toro E, Rovira JC, Vicente-Agullo F, Chapuli J, Juiz JM, Sala S, Sala F, Ballesta JJ, Criado M (1997) Neuronal nicotinic acetylcholine receptors on bovine chromaffin cells: cloning, expression, and genomic organization of receptor subunits. J Neurochem 68:488–497CrossRefPubMedGoogle Scholar
- 11.Colomer C, Olivos-Ore LA, Vincent A, McIntosh JM, Artalejo AR, Guerineau NC (2010) Functional characterization of alpha9-containing cholinergic nicotinic receptors in the rat adrenal medulla: implication in stress-induced functional plasticity. J Neurosci 30:6732–6742CrossRefPubMedPubMedCentralGoogle Scholar
- 12.Criado M, Domínguez del Toro E, Carrasco-Serrano C, Smillie FI, Juíz JM, Viniegra S, Ballesta JJ (1997) Differential expression of alpha-bungarotoxin-sensitive neuronal nicotinic receptors in adrenergic chromaffin cells: a role for transcription factor Egr-1. J Neurosci 17:6554–6564PubMedGoogle Scholar
- 13.Del Barrio L, Egea J, Leon R, Romero A, Ruiz A, Montero M, Alvarez J, López MG (2011) Calcium signalling mediated through alpha7 and non-alpha7 nAChR stimulation is differentially regulated in bovine chromaffin cells to induce catecholamine release. Br J Pharmacol 162:94–110CrossRefPubMedPubMedCentralGoogle Scholar
- 18.García-Guzmán M, Sala F, Sala S, Campos-Caro A, Stuhmer W, Gutierrez LM, Criado M (1995) alpha-Bungarotoxin-sensitive nicotinic receptors on bovine chromaffin cells: molecular cloning, functional expression and alternative splicing of the alpha 7 subunit. Eur J Neurosci 7:647–655CrossRefPubMedGoogle Scholar
- 20.Hone AJ, Ruiz M, Scadden M, Christensen S, Gajewiak J, Azam L, McIntosh JM (2013) Positional scanning mutagenesis of α-conotoxin PeIA identifies critical residues that confer potency and selectivity for α6/α3β2β3 and α3β2 nicotinic acetylcholine receptors. J Biol Chem 288:25428–25439Google Scholar
- 21.Hone AJ, McIntosh JM, Azam L, Lindstrom J, Lucero L, Whiteaker P, Passas J, Blazquez J, Albillos A (2015) α-Conotoxins identify the α3β4 subtype as the predominant nicotinic acetylcholine receptor expressed in human adrenal chromaffin cells. Mol Pharmacol 88:881–893CrossRefPubMedPubMedCentralGoogle Scholar
- 24.Innocent N, Livingstone PD, Hone A, Kimura A, Young T, Whiteaker P, McIntosh JM, Wonnacott S (2008) Alpha-conotoxin Arenatus IB[V11L,V16D] [corrected] is a potent and selective antagonist at rat and human native alpha7 nicotinic acetylcholine receptors. J Pharmacol Exp Ther 327:529–537CrossRefPubMedPubMedCentralGoogle Scholar
- 27.López MG, Montiel C, Herrero CJ, García-Palomero E, Mayorgas I, Hernandez-Guijo JM, Villarroya M, Olivares R, Gandia L, McIntosh JM, Olivera BM, García AG (1998) Unmasking the functions of the chromaffin cell alpha7 nicotinic receptor by using short pulses of acetylcholine and selective blockers. Proc Natl Acad Sci U S A 95:14184–14189CrossRefPubMedPubMedCentralGoogle Scholar
- 28.Luo S, Kulak JM, Cartier GE, Jacobsen RB, Yoshikami D, Olivera BM, McIntosh JM (1998) alpha-conotoxin AuIB selectively blocks alpha3 beta4 nicotinic acetylcholine receptors and nicotine-evoked norepinephrine release. J Neurosci 18:8571–8579Google Scholar
- 29.Luo S, Zhangsun D, Wu Y, Zhu X, Hu Y, McIntyre M, Christensen S, Akcan M, Craik DJ, McIntosh JM (2013) Characterization of a novel a-conotoxin from conus textile that selectively targets a6/a3b2b3 nicotinic acetylcholine receptors. J Biol Chem 288:894–902Google Scholar
- 35.Pérez-Alvarez A, Hernandez-Vivanco A, Gregorio SA, Tabernero A, McIntosh JM, AlbillosA (2012a) Pharmacological characterization of native α7 nAChRs and their contribution to depolarization-elicited exocytosis in human chromaffin cells. Br J Pharmacol 165:908–921CrossRefPubMedPubMedCentralGoogle Scholar
- 44.Smith NJ, Hone AJ, Memon T, Bossi S, Smith TE, McIntosh JM, Olivera BM, Teichert RW (2013) Comparative functional expression of nAChR subtypes in rodent DRG neurons. Front Cell Neurosci 7:225Google Scholar