Artículos de revistas
Tonic and phasic receptor neurons in the vertebrate olfactory epithelium
Fecha
2003Registro en:
Biophysical Journal, Volumen 84, Issue 6, 2018, Pages 4167-4181
00063495
10.1016/S0006-3495(03)75141-8
Autor
Madrid, Rodolfo
Sanhueza, Magdalena
Alvarez, Osvaldo
Bacigalupo Vicuña, Juan
Institución
Resumen
Olfactory receptor neurons (ORNs) respond to odorants with characteristic patterns of action potentials that are relevant for odor coding. Prolonged odorant exposures revealed three populations of dissociated toad ORNs, which were mimicked by depolarizing currents: tonic (TN, displaying sustained firing, 49% of 102 cells), phasic (PN, exhibiting brief action potential trains, 36%) and intermediate neurons (IN, generating trains longer than PN, 15%). We studied the biophysical properties underlying the differences between TNs and PNs, the most extreme cases among ORNs. TNs and PNs possessed similar membrane capacitances (∼4 pF), but they differed in resting potential (-82 versus -64 mV), input resistance (4.2 versus 2.9 GΩ) and unspecific current, Iu (TNs: 0 < Iu ≤ 1 pA/pF; and PNs: Iu > 1 pA/pF). Firing behavior did not correlate with differences in voltage-gated conductances. We developed a mathematical model that accurately simulates tonic and phasic patterns. Whole cell recordings f