Action of cismethrin and deltamethrin on functional attributes of isolated presynaptic nerve terminals from rat brain |
| |
Institution: | 1. School of Pharmacy, University of Camerino, Camerino 62032, MC, Italy;2. Department of Life and Environmental Sciences, Polytechnic University of Marche, 60128, AN, Italy;3. Department of Biochemistry and Molecular Biology, University of Valencia and INCLIVA Biomedical Research Institute, Valencia, Spain;1. Institut National de la Recherche Scientifique, Institut Armand-Frappier, Laval, QC, Canada;2. INRS-ETE, Université du Québec, Québec, Canada |
| |
Abstract: | Isolated presynaptic nerve terminals (synaptosomes) prepared from rat brain were used to evaluate the actions of a tremor (T)-syndrome (cismethrin) and a choreoathetosis-salivation (CS)-syndrome (deltamethrin) pyrethroid on the functional attributes of synaptosomes by measuring calcium influx and endogenous neurotransmitter (l-glutamate) release with fluorescent assays. Both cismethrin and deltamethrin stimulated calcium influx, however, only deltamethrin enhanced Ca2+-dependent neurotransmitter release and its action was stereospecific, concentration-dependent, stimulated by depolarization, unaltered by tetrodotoxin, and blocked by ω-conotoxin GVIA. Our results delineate a separate action of deltamethrin on presynaptic nerve terminals from that elicited by cismethrin and implicate Cav2.2 calcium channels as target sites for deltamethrin that is consistent with the observed in vivo release of neurotransmitter at the onset of convulsive symptom caused by CS-syndrome pyrethroids. This information will allow a more complete understanding of the molecular and cellular nature of pyrethroid-induced neurotoxicity and expands our knowledge of the structure–activity relationships of pyrethroids in regards to their action on voltage-sensitive calcium channels. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|