Cadmium ions modulate GABA induced currents in molluscan neurons

G. Molnár, J. Györi, J. Salánki, Katalin S-Rózsa

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The effect of Cd2+, as one of the most widespread toxic environmental pollutants, was studied on γ-aminobutyric acid (GABA) evoked responses of identified neurons in the central nervous system of the pond snail, Lymnaea stagnalis L. (Gastropoda). In the experiments, the modulation of the action of GABA both on neuronal activity (current clamp recording) and on the a GABA activated membrane Cl--current (voltage clamp studies) has been shown. It was found that: 1. GABA could evoked three different various types of response in GABA sensitive neurons: i) hyperpolarization with strong inhibition of ongoing spike activity, ii) short depolarization with an increase of spike the activity, iii) biphasic respone with a short excitation followed by a more prolonged long inhibition. 2. In low-Cl- solution the inhibitory action of GABA was reduced or eliminated, but the excitatory one was not or only moderately affected. 3. CdCl2 inhibited the GABA evoked hyperpolarization, but left intact or only slightly reduced the excitation evoked by GABA. 4. The inward Cl--current evoked by GABA at a -75 mV holding potential was slightly augmented in the presence of 1 μmol/l Cd2+, but was reduced or blocked at higher cadmium concentrations. The effect of Cd2+ was concentration and time dependent. 5. Parallel with reducing the GABA evoked current, cadmium increased both the time to peak and the half inactivation time of the current. 6. CdCl2 alone, in 50 μmol/l concentration, induced a 1-2 nA inward current. The blocking effect of cadmium on GABA activated inhibitory processes can be an important component of the neuro-toxic effects of this heavy metal ion.

Original languageEnglish
Pages (from-to)105-123
Number of pages19
JournalActa Biologica Hungarica
Volume53
Issue number1-2
DOIs
Publication statusPublished - 2002

Fingerprint

gamma-aminobutyric acid
Induced currents
Cadmium
gamma-Aminobutyric Acid
Neurons
cadmium
neurons
Ions
ions
ion
nervous system
snail
Cadmium Chloride
pond
heavy metal
Poisons
membrane
Clamping devices
pollutant
acid

Keywords

  • Cd, Cl
  • Current
  • GABA
  • Lymnaea stagnalis L.

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)

Cite this

Cadmium ions modulate GABA induced currents in molluscan neurons. / Molnár, G.; Györi, J.; Salánki, J.; S-Rózsa, Katalin.

In: Acta Biologica Hungarica, Vol. 53, No. 1-2, 2002, p. 105-123.

Research output: Contribution to journalArticle

Molnár, G. ; Györi, J. ; Salánki, J. ; S-Rózsa, Katalin. / Cadmium ions modulate GABA induced currents in molluscan neurons. In: Acta Biologica Hungarica. 2002 ; Vol. 53, No. 1-2. pp. 105-123.
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