Tan Z Y, Xiao H, Mao X, Wang C Y, Zhao Z Q, Ji Y H
Shanghai Institute of Physiology, Chinese Academy of Sciences, 320 Yue-Yang Road, 200031, Shanghai, People's Republic of China.
Neuropharmacology. 2001 Mar;40(3):352-7. doi: 10.1016/s0028-3908(00)00168-4.
Buthus martensi Karsch IT2 (BmK IT2), a scorpion neurotoxin, was found to display a biphasic inhibitory effect on the C component of the rat nociceptive flexion reflex by subcutaneous injection in vivo, and also on the total Na(+) currents of rat dorsal root ganglion neurons using whole-cell patch clamping. BmK IT2 blocked the tetrodotoxin-resistant (TTX-R) component of the Na(+) currents with a degree of selectivity. The partial block of the TTX-R Na(+) currents, brought about by 0.01 microg/microl BmK IT2, reversed less rapidly and completely than the partial block of the tetrodotoxin-sensitive (TTX-S) current brought about by the same concentration of BmK IT2. These results suggest that the inhibition of the rat nociceptive flexion reflex by BmK IT2 may be attributed to modulation of the different voltage-gated Na(+) channels.
东亚钳蝎毒素IT2（BmK IT2）是一种蝎神经毒素，通过体内皮下注射发现其对大鼠伤害性屈曲反射的C成分具有双相抑制作用，并且使用全细胞膜片钳技术对大鼠背根神经节神经元的总钠电流也有双相抑制作用。BmK IT2以一定的选择性阻断钠电流的河豚毒素抗性（TTX-R）成分。由0.01μg/μl BmK IT2引起的TTX-R钠电流的部分阻断，其逆转速度和完全程度低于相同浓度BmK IT2引起的河豚毒素敏感性（TTX-S）电流的部分阻断。这些结果表明，BmK IT2对大鼠伤害性屈曲反射的抑制作用可能归因于对不同电压门控钠通道的调节。
