Granja, RicardoFernández-Fernández, José Manuel, 1967-Izaguirre, VictorGonzález García, CarmenCeña, Valentin2016-01-212016-01-211995Granja R, Fernández-Fernández JM, Izaguirre V, González-García C, Ceña V. omega-Agatoxin IVA blocks nicotinic receptor channels in bovine chromaffin cells. FEBS letters. 1995;362(1):15-8. DOI: 10.1016/0014-5793(95)00149-40014-5793http://hdl.handle.net/10230/25632We have studied the contribution of P-type voltage-dependent Ca2+ channels to both catacholamine (CA) and ATP secretion from bovine chromaffin cells induced by high K+ or nicotine using omega-agatoxin IVA, a selective blocker of P-type voltage-dependent Ca2+ channels. We found that high K+ (75 mM) induced the release of about 13% of norepinephrine, 5% epinephrine and 11% ATP, and that omega-agatoxin (100 nM) did not affect this secretion. However, both nicotine-induced CA and ATP secretion were significantly blocked (about 50%) by omega-agatoxin IVA (100 nM). In addition, this toxin also reversibly blocked (about 70%) the inward current induced by nicotine in bovine chromaffin cells. The results suggest that, besides its known action of blocking P-type voltage-dependent channels, omega-agatoxin is a potent and reversible blocker of the nicotinic receptor channel in chromaffin cells, and that this action would explain the blockade of nicotine-induced secretion.application/pdfeng© Elsevier This is the published version of an article http://dx.doi.org/10.1016/0014-5793(95)00149-4 that appeared in the journal Developmental cell. It is published in an Open Archive under an Elsevier user license. Details of this licence are available here: http://www.elsevier.com/about/open-access/open-access-policies/oa-license-policy/elsevier-user-licenseCanals de potassiNicotinainfo:eu-repo/semantics/articlehttp://dx.doi.org/10.1016/0014-5793(95)00149-4Calcium channelP-typeNicotinic receptoromega-Agatoxin IVASecretionChromaffin cellinfo:eu-repo/semantics/openAccess