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β－银环蛇神经毒素阻遏神经肌肉接头递质释放的作用机理，可能与它结合于一种突触前的电压依赖的Ｋ~＋通道有关。本文报告了从大鼠膈肌膜组分中用去垢剂ＴｒｉｔｏｎＸ－１００增溶抽提β－银环蛇毒素结合蛋白的结果。这种结合蛋白抽提液的比结合活性为２００－４００ｆｍｏｌ／ｍｇ蛋白，比膜制备物的比结合活力提高约一倍。抽提得率为５０％－７０％。抽提液与~（１２５）Ｉ标记的β－银环蛇毒素的结合可被曼巴蛇神经毒素（ｄｅｎｄｒｏｔｏｘｉｎ）完全抑制，其ＩＣ_（５０）约８×１０~（－８）ｍｏｌ／Ｌ。但另一种β型神经毒素，β－蝮蛇神经毒素（β－ａｇｋｉｓｔｒｏｄｏｔｏｋｉｎ）却完全不能抑制这种结合。这提示，β－蝮蛇毒素与β－银环蛇毒素具有不同的作用位点。
The mechanism by which β-bungarotoxin blocks the neurotransmitter neurotransmitter release may be related to its binding to a presynaptic voltage-dependent K ~ + channel. This paper reports the results of the solubilization of β-bungarotoxin binding protein with the detergent TritonX-100 from the rat diaphragmatic membrane fraction. The specific binding activity of this binding protein extract is 200-400 fmol / mg protein, which is approximately double the specific binding activity of the membrane preparation. Extraction rate of 50% -70%. The binding of the extract with ~ (125) I labeled β-bungarotoxin was completely inhibited by dendrotoxin with an IC 50 of about 8 × 10 -8 mol / L. However, β-agkistrodotokin, another β-type neurotoxin, failed to inhibit this binding at all. This suggests that β-viperns and β-bungarotoxin have different sites of action.