Frequency-dependent effects of the pyrethroid insecticide decamethrin in frog myelinated nerve fibres.
The pyrethroid insecticide decamethrin (10(-6) M) caused a frequency-dependent depression of the action potential in frog myelinated nerve fibres which was associated with a progressive membrane depolarisation brought about by summation of depolarising after-potentials. Voltage clamp experiments with single nodes of Ranvier showed that this afterpotential was most probably due to a long-lasting prolongation of the transient increase in sodium permeability of the membrane. The results indicate that decamethrin, like the other pyrethroids, specifically affects the sodium channels of the nerve membrane.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001001:Anura; D004558:Electric Stimulation; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009413:Nerve Fibers, Myelinated / Q000187:drug effects*; D009570:Nitriles; D011722:Pyrethrins / Q000494:pharmacology*; D011901:Ranvier's Nodes / Q000187:drug effects; D014981:Xenopus
D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin