D'Suze G, Corona F, Possani L D, Sevcik C
Instituto Venezolano de Investigaciones Cientificas, CBB, Laboratory of Cellular Neuropharmacology, Caracas, Venezuela.
Toxicon. 1996 May;34(5):591-8. doi: 10.1016/0041-0101(95)00156-5.
Tityus discrepans venom was fractionated by gel filtration on Sephadex G-50 column. The peptides in fraction II from Sephadex were further purified by high performance liquid chromatography, through a C4 reverse-phase column. Lethality of purified peptides was determined by injection into mice and crabs, and their effects were verified electrophysiologically on frog (Hyla crepitans) sartorius neuromuscular junction. Toxins having retention times between 39.6 and 40.7 min depolarized the muscle membrane and caused acetylcholine release at the endplate. The toxin eluted at 42.67 min increased the frequency of miniature endplate potentials without depolarizing muscle fibres. The four most active toxins were reduced, carboxymethylated and sequenced by automatic Edman degradation and named TdII-1 to II-4. Toxin gamma from Tityus serrulatus venom and the toxins from T. discrepans venom were found to be structurally distinct. TdII-1 to II-4 lack the pancreatic effects of T. serrulatus' toxin gamma; yet, the five toxins act on Na+ channels.
差异毒蝎（Tityus discrepans）毒液通过在葡聚糖G - 50柱上进行凝胶过滤进行分离。葡聚糖分离物II中的肽通过C4反相柱进行高效液相色谱进一步纯化。通过注射到小鼠和螃蟹体内测定纯化肽的致死性，并在青蛙（雨蛙，Hyla crepitans）缝匠肌神经肌肉接头处进行电生理验证其作用。保留时间在39.6至40.7分钟之间的毒素使肌膜去极化并导致终板处乙酰胆碱释放。在42.67分钟洗脱的毒素增加了微小终板电位的频率，而不使肌纤维去极化。四种活性最高的毒素经还原、羧甲基化处理，并通过自动埃德曼降解法测序，命名为TdII - 1至II - 4。发现锯齿毒蝎（Tityus serrulatus）毒液中的毒素γ与差异毒蝎毒液中的毒素在结构上不同。TdII - 1至II - 4缺乏锯齿毒蝎毒素γ的胰腺效应；然而，这五种毒素均作用于钠离子通道。
