title: α-Dendrotoxin inhibits the ASIC current in dorsal root ganglion neurons from rat.
abstract: Dendrotoxins are a group of peptide toxins purified from the venom of several mamba snakes. α-Dendrotoxin (α-DTx, from the Eastern green mamba Dendroaspis angusticeps) is a well-known blocker of voltage-gated K(+) channels and specifically of K(v)1.1, K(v)1.2 and K(v)1.6. In this work we show that α-DTx inhibited the ASIC currents in DRG neurons (IC50=0.8 μM) when continuously perfused during 25 s (including a 5 s pulse to pH 6.1), but not when co-applied with the pH drop. Additionally, we show that α-DTx abolished a transient component of the outward current that, in some experiments, appeared immediately after the end of the acid pulse. Our data indicate that α-DTx inhibits ASICs in the high nM range while some Kv are inhibited in the low nM range. The α-DTx selectivity and its potential interaction with ASICs should be taken in consideration when DTx is used in the high nM range.
authors: Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), 14 sur 6301, CU, San Manuel, Puebla, Pue., CP 72570, Mexico. Electronic address: abaezc@hotmail.com.
authors: Adriana
authors: A
authors: Báez
authors: Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), 14 sur 6301, CU, San Manuel, Puebla, Pue., CP 72570, Mexico. Electronic address: emilio.salceda@gmail.com.
authors: Emilio
authors: E
authors: Salceda
authors: Faculty of Chemistry, UDELAR, Av. Gral., Flores, Montevideo 2124, Uruguay. Electronic address: martinflo1@gmail.com.
authors: Martín
authors: M
authors: Fló
authors: Institut Pasteur de Montevideo, Mataojo 2020, Montevideo 11400, Uruguay. Electronic address: mgrana@pasteur.edu.uy.
authors: Martín
authors: M
authors: Graña
authors: Faculty of Chemistry, UDELAR, Av. Gral., Flores, Montevideo 2124, Uruguay. Electronic address: cfernan@fq.edu.uy.
authors: Cecilia
authors: C
authors: Fernández
authors: Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), 14 sur 6301, CU, San Manuel, Puebla, Pue., CP 72570, Mexico. Electronic address: axolotl_56@yahoo.com.mx.
authors: Rosario
authors: R
authors: Vega
authors: Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), 14 sur 6301, CU, San Manuel, Puebla, Pue., CP 72570, Mexico. Electronic address: esoto24@gmail.com.
authors: Enrique
authors: E
authors: Soto
mesh_terms: D062565:Acid Sensing Ion Channels / Q000502:physiology*; D000818:Animals; D002478:Cells, Cultured; D004546:Elapid Venoms / Q000494:pharmacology*; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D026902:Potassium Channel Blockers / Q000494:pharmacology*; D020318:Rats, Long-Evans
chemical_list: D062565:Acid Sensing Ion Channels; D004546:Elapid Venoms; D026902:Potassium Channel Blockers; C020273:dendrotoxin
keywords: APETx2; ASIC; K(Na); K(v); Kunitz domain; Proton gated; Slack; Slick