Barhanin J, Meiri H, Romey G, Pauron D, Lazdunski M
Proc Natl Acad Sci U S A. 1985 Mar;82(6):1842-6. doi: 10.1073/pnas.82.6.1842.
We describe the properties of a monoclonal antibody against the Na+ channel. The antibody, 72.38, competitively inhibited (Ki = 1.5 X 10(-9) M) the binding of an 125I-labeled toxin from the Brazilian scorpion Tityus serrulatus (125I-TiTX gamma) to Na+ channels of rat brain membranes. No significant inhibition of binding of a number of other Na+ channel toxins was observed. The inhibition of 125I-TiTX gamma binding also was observed with the solubilized Na+ channel from rat brain membranes (Ki = 2 X 10(-9) M). Antibody 72.38 antagonized 125I-TiTX gamma binding to Na+ channels from different animal species (fish, avian, and mammalian) and from different tissues (electroplax, brain, heart, and muscle). Moreover, 72.38 has been used for immunofluorescence labeling of Na+ channels in rat sciatic nodes of Ranvier and cultured dorsal root ganglion cells. Electrophysiological experiments on rat muscle cells fully confirmed the similarity between TiTX gamma and 72.38 seen in binding experiments. Both produce slow oscillations of the membrane potential accompanied by bursts of action potentials which are due to a selective action on the Na+ channel. TiTX gamma and 72.38 are without effect on the ion selectivity of the Na+ channel, but they both drastically change the voltage-dependence of activation and inactivation of the Na+ channel.
我们描述了一种抗钠离子通道单克隆抗体的特性。该抗体72.38能竞争性抑制（Ki = 1.5×10⁻⁹ M）来自巴西蝎子锯齿脂鲤（125I-TiTXγ）的125I标记毒素与大鼠脑膜钠离子通道的结合。未观察到对其他多种钠离子通道毒素结合的显著抑制作用。在大鼠脑膜溶解的钠离子通道中也观察到了对125I-TiTXγ结合的抑制作用（Ki = 2×10⁻⁹ M）。抗体72.38能拮抗125I-TiTXγ与不同动物物种（鱼类、禽类和哺乳动物）以及不同组织（电鳐、脑、心脏和肌肉）的钠离子通道的结合。此外，72.38已用于大鼠坐骨神经郎飞结和培养的背根神经节细胞中钠离子通道的免疫荧光标记。对大鼠肌肉细胞的电生理实验充分证实了在结合实验中所见的TiTXγ和72.38之间的相似性。两者都会产生膜电位的缓慢振荡，并伴有动作电位的爆发，这是由于对钠离子通道的选择性作用所致。TiTXγ和72.38对钠离子通道的离子选择性没有影响，但它们都极大地改变了钠离子通道激活和失活的电压依赖性。
