Effect of deltamethrin on transient outward currents in identified snail neurons.
1. The effect of a pyrethroid insecticide deltamethrin was investigated on transient outward potassium currents of identified snail (Helix pomatia) neurones LPa1 and RPa3. 2. In 5 x 10(-5)M concentration the deltamethrin decreased the IA amplitude and the slope of I-V curve. The activation variable was shifted left along the voltage axis by 10-20 mV, while the inactivation variable remained unchanged. 3. Time constant of inactivation decreased, and the relaxation of IA described by one exponential. "Modified" ionic channel fraction was not observed. 4. It is suggested that deltamethrin acts on IA channels through a different molecular mechanism to INa channels, since not only the gating machinery but the permeability of the channels were influenced.
Kiss
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Balaton Limnological Research Institute, Hungarian Academy of Sciences, Tihany.
D000818:Animals; D006372:Helix, Snails; D066298:In Vitro Techniques; D007306:Insecticides; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D009570:Nitriles; D011188:Potassium / Q000378:metabolism; D011722:Pyrethrins / Q000633:toxicity*
D007306:Insecticides; D007473:Ion Channels; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin; D011188:Potassium