کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2590006 1562061 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Agonist actions of clothianidin on synaptic and extrasynaptic nicotinic acetylcholine receptors expressed on cockroach sixth abdominal ganglion
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست بهداشت، سم شناسی و جهش زایی
پیش نمایش صفحه اول مقاله
Agonist actions of clothianidin on synaptic and extrasynaptic nicotinic acetylcholine receptors expressed on cockroach sixth abdominal ganglion
چکیده انگلیسی

Clothianidin is new neonicotinoid insecticide acting selectively on insect nicotinic acetylcholine receptors (nAChRs). Its effects on nAChRs expressed on cercal afferent/giant interneuron synapses and DUM neurons have been studied using mannitol-gap and whole-cell patch-clamp techniques, respectively. Bath-application of clothianidin-induced dose-dependent depolarizations of cockroach cercal afferent/giant interneuron synapses which were not reversed after wash-out suggesting a strong desensitization of postsynaptic interneurons at the 6th abdominal ganglion (A6). Clothinidin activity on the nerve preparation was characterized by an increased firing rate of action potentials which then ceased when the depolarization reached a peak. Clothianidin responses were insensitive to all muscarinic antagonists tested but were blocked by co-application of specific nicotinic antagonists methyllicaconitine, α-bungarotoxin and d-tubocurarine.In a second round of experiment, clothianidin actions were tested on DUM neurons isolated from the A6. There was a strong desensitization of nAChRs which was not affected by muscarinic antagonists, pirenzepine and atropine, but was reduced with nicotinic antagonist α-bungarotoxin. In addition, clothianidin-induced currents were completely blocked by methyllicaconitine suggesting that (1) clothianidin acted as a specific agonist of nAChR subtypes and (2) a small proportion of receptors blocked by MLA was insensitive to α-bungarotoxin. Moreover, because clothianidin currents were blocked by d-tubocurarine and mecamylamine, we provided that clothianidin was an agonist of both nAChRs: imidacloprid-sensitive nAChR1 and -insensitive nAChR2 subtypes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: NeuroToxicology - Volume 30, Issue 6, November 2009, Pages 1045–1052
نویسندگان
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