van Huizen F, Romijn H J, Habets A M
Brain Res. 1985 Mar;351(1):67-80. doi: 10.1016/0165-3806(85)90232-9.
Reaggregated occipital cortex cells of 19-day-old fetal rats were grown in a serum-free, chemically defined medium, and chronically exposed to impulse-blocking levels of tetrodotoxin (TTX) in order to study the role of bioelectric activity in synaptogenesis. As judged by phase-contrast microscopy, no differences were noticed in the development of neuronal networks in the TTX-treated vs control cultures. In addition, when TTX was withdrawn from experimental cultures at any stage of development, bioelectric activity qualitatively comparable to that of the control cultures appeared within 1 min. However, quantitative stereological EM analysis revealed a significant retardation in synapse formation and ultrastructural maturation of synaptic junctions during the first 3 weeks. Around 23 days in vitro, the central zone of the reaggregates in control cultures started to degenerate, but not earlier then day 27 in TTX-treated cultures. During this time, the control, but not the experimental cultures showed (in intact tissue regions mainly situated at the outside of the aggregates) a large and selective loss of spine synapses. It is concluded that functional blockade not only retards the early growth and maturation of synaptic networks but also prevents the later occurring selective loss of spine synapses.
将19日龄胎鼠的枕叶皮质细胞重新聚集后，在无血清、化学成分明确的培养基中培养，并长期暴露于河豚毒素（TTX）的冲动阻断水平，以研究生物电活动在突触形成中的作用。通过相差显微镜判断，在TTX处理的培养物与对照培养物中，神经网络的发育没有差异。此外，在发育的任何阶段从实验培养物中撤去TTX时，在1分钟内就会出现与对照培养物在质量上相当的生物电活动。然而，定量立体学电子显微镜分析显示，在最初3周内，突触形成和突触连接的超微结构成熟明显延迟。在体外培养约23天时，对照培养物中重新聚集物的中心区域开始退化，但在TTX处理的培养物中不早于第27天。在此期间，对照培养物（但实验培养物未出现）在（主要位于聚集物外部的完整组织区域）显示出大量且选择性的棘突触丧失。得出的结论是，功能阻断不仅会延迟突触网络的早期生长和成熟，还会阻止后期发生的选择性棘突触丧失。
