کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2569556 1128536 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Divergent actions of the pyrethroid insecticides S-bioallethrin, tefluthrin, and deltamethrin on rat Nav1.6 sodium channels
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست بهداشت، سم شناسی و جهش زایی
پیش نمایش صفحه اول مقاله
Divergent actions of the pyrethroid insecticides S-bioallethrin, tefluthrin, and deltamethrin on rat Nav1.6 sodium channels
چکیده انگلیسی

We expressed rat Nav1.6 sodium channels in combination with the rat β1 and β2 auxiliary subunits in Xenopus laevis oocytes and evaluated the effects of the pyrethroid insecticides S-bioallethrin, deltamethrin, and tefluthrin on expressed sodium currents using the two-electrode voltage clamp technique. S-Bioallethrin, a type I structure, produced transient modification evident in the induction of rapidly decaying sodium tail currents, weak resting modification (5.7% modification at 100 μM), and no further enhancement of modification upon repetitive activation by high-frequency trains of depolarizing pulses. By contrast deltamethrin, a type II structure, produced sodium tail currents that were ~ 9-fold more persistent than those caused by S-bioallethrin, barely detectable resting modification (2.5% modification at 100 μM), and 3.7-fold enhancement of modification upon repetitive activation. Tefluthrin, a type I structure with high mammalian toxicity, exhibited properties intermediate between S-bioallethrin and deltamethrin: intermediate tail current decay kinetics, much greater resting modification (14.1% at 100 μM), and 2.8-fold enhancement of resting modification upon repetitive activation. Comparison of concentration–effect data showed that repetitive depolarization increased the potency of tefluthrin ~ 15-fold and that tefluthrin was ~ 10-fold more potent than deltamethrin as a use-dependent modifier of Nav1.6 sodium channels. Concentration–effect data from parallel experiments with the rat Nav1.2 sodium channel coexpressed with the rat β1 and β2 subunits in oocytes showed that the Nav1.6 isoform was at least 15-fold more sensitive to tefluthrin and deltamethrin than the Nav1.2 isoform. These results implicate sodium channels containing the Nav1.6 isoform as potential targets for the central neurotoxic effects of pyrethroids.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Toxicology and Applied Pharmacology - Volume 247, Issue 3, 15 September 2010, Pages 229–237
نویسندگان
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