High-gain, low-noise amplification in olfactory transduction.
AUTOR(ES)
Kleene, S J
RESUMO
It is desirable that sensory systems use high-gain, low-noise amplification to convert weak stimuli into detectable signals. Here it is shown that a pair of receptor currents underlying vertebrate olfactory transduction constitutes such a scheme. The primary receptor current is an influx of Na+ and Ca2+ through cAMP-gated channels in the olfactory cilia. External divalent cations improve the signal-to-noise properties of this current, reducing the mean current and the current variance. As Ca2+ enters the cilium, it gates Cl- channels, activating a secondary depolarizing receptor current. This current amplifies the primary current, but introduces little additional noise. The system of two currents plus divalent cations in the mucus produces a large receptor current with very low noise.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1181007Documentos Relacionados
- Co-Design of a GPS Antenna Low-Noise Amplifier Front-End Circuit
- Asymmetry and external noise-induced free energy transduction.
- A High-Gain Hemispherical Dielectric Lens Antenna Operating Simultaneously in Narrowband or Wideband for X-band Applications
- Phosphorylation in halobacterial signal transduction.
- Stochastic free energy transduction.