title: The effects of huwentoxin-I on the voltage-gated sodium channels of rat hippocampal and cockroach dorsal unpaired median neurons.
abstract: Huwentoxin-I (HWTX-I) is a 33-residue peptide isolated from the venom of Ornithoctonus huwena and could inhibit TTX-sensitive voltage-gated sodium channels and N-type calcium channels in mammalian dorsal root ganglion (DRG) neurons. However, the effects of HWTX-I on mammalian central neuronal and insect sodium channel subtypes remain unknown. In this study, we found that HWTX-I potently inhibited sodium channels in rat hippocampal and cockroach dorsal unpaired median (DUM) neurons with the IC(50) values of 66.1±5.2 and 4.80±0.58nM, respectively. Taken together with our previous work on DRG neurons (IC(50)≈55nM), the order of sodium channel sensitivity to HWTX-I inhibition was insect central DUM≫mammalian peripheral>mammalian central neurons. HWTX-I exhibited no effect on the steady-state activation and inactivation of sodium channels in rat hippocampal and cockroach DUM neurons.
authors.affiliation: The College of Life Science, Hunan Normal University, Changsha, People's Republic of China.
authors.forename: Meichi
authors.initials: M
authors.lastname: Wang
authors.forename: Mingqiang
authors.initials: M
authors.lastname: Rong
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Xiao
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003058:Cockroaches / Q000166:cytology*; D004594:Electrophysiology; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D030162:Reptilian Proteins / Q000138:chemical synthesis / Q000494:pharmacology*; D015222:Sodium Channels / Q000378:metabolism*; D013111:Spider Venoms / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D030162:Reptilian Proteins; D015222:Sodium Channels; D013111:Spider Venoms; C083624:huwentoxin I