Patrick J, Heinemann S F, Lindstrom J, Schubert D, Steinbach J H
Proc Natl Acad Sci U S A. 1972 Oct;69(10):2762-6. doi: 10.1073/pnas.69.10.2762.
Acquisition of acetylcholine receptors during differentiation of a clonal myoblast cell line was monitored with a neurotoxin isolated from venom of the Indian Cobra Naja naja. Toxin bound specifically and reversibly to acetylcholine receptors of the differentiated cells. Specificity of the binding reaction was assayed by measurement of the ability of various cholinergic agonists and antagonists to compete with neurotoxin for its binding site. The rate of toxin binding paralleled the rate of inactivation of functional acetylcholine receptors, as measured by iontophoretic application of acetylcholine. Bound toxin was released from the cells with a half-life of about 7 hr. This release was not associated with a decrease in the total number of toxin-binding sites. A slow hyperpolarizing response to acetylcholine seen in myoblasts was insensitive to toxin; the appearance of toxin-binding sites parallels the appearance of fused fibers during differentiation of the muscle cells in tissue culture.
利用从印度眼镜蛇眼镜王蛇毒液中分离出的一种神经毒素，监测克隆成肌细胞系分化过程中乙酰胆碱受体的获得情况。毒素与分化细胞的乙酰胆碱受体特异性且可逆地结合。通过测量各种胆碱能激动剂和拮抗剂与神经毒素竞争其结合位点的能力，来检测结合反应的特异性。毒素结合速率与功能性乙酰胆碱受体失活速率平行，这是通过离子电泳施加乙酰胆碱来测量的。结合的毒素以约7小时的半衰期从细胞中释放出来。这种释放与毒素结合位点总数的减少无关。成肌细胞中观察到的对乙酰胆碱的缓慢超极化反应对毒素不敏感；在组织培养中肌肉细胞分化过程中，毒素结合位点的出现与融合纤维的出现平行。
