Azimi-Zonooz A, Litzinger M J
Department of Biology, University of Utah, Salt Lake City 84112.
Int J Dev Neurosci. 1992 Oct;10(5):447-51. doi: 10.1016/0736-5748(92)90035-x.
omega-Conotoxin CVIA, a 27 amino acid neuropeptide toxin believed to target voltage sensitive calcium channels (Cruz et al., 1987, Biochemistry 26 (3), 820-824) was bound to developing chick brain at embryonic day 9-post hatch day 10. A two-fold increase was observed in omega-Conotoxin binding sites around chick hatching, embryonic days 18-20. Depolarization induced 45Ca fluxes also increased around hatching. omega-Conotoxins block > or = 80% of these 45Ca fluxes throughout development. Competition binding did not detect large differences in the binding affinity of sites during development. We conclude from these data that the increases in omega-Conotoxin binding sites and 45Ca fluxes around chick hatching are related to one of the presynaptic mechanisms of neuronal maturation necessary for normal neuronal function and chick behavior after hatching.
ω-芋螺毒素CVIA是一种由27个氨基酸组成的神经肽毒素，据信其作用靶点是电压敏感性钙通道（Cruz等人，1987年，《生物化学》26(3)，820 - 824），它在胚胎第9天至孵化后第10天与发育中的鸡脑结合。在鸡孵化前后，即胚胎第18 - 20天，观察到ω-芋螺毒素结合位点增加了两倍。孵化前后，去极化诱导的45Ca通量也增加。在整个发育过程中，ω-芋螺毒素可阻断≥80%的这些45Ca通量。竞争结合实验未检测到发育过程中各结合位点的结合亲和力存在显著差异。从这些数据我们得出结论，鸡孵化前后ω-芋螺毒素结合位点和45Ca通量的增加与正常神经元功能及鸡孵化后行为所必需的神经元成熟的突触前机制之一有关。
