Volatile Anesthetics Rapidly Increase Dendritic Spine Density in the Rat Medial Prefrontal Cortex during Synaptogenesis
Volatile Anesthetics Rapidly Increase Dendritic Spine Density in the Rat Medial Prefrontal Cortex during Synaptogenesis
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DOI：
10.1097/aln.0b013e3181cd7942
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发表时间：
2010-03-01
期刊：
影响因子：
8.8
通讯作者：
Vutskits, Laszlo
中科院分区：
文献类型：
--
作者：
Briner, Adrian;De Roo, Mathias;Vutskits, Laszlo
背景资料：最近的实验观察表明，除了诱导神经细胞凋亡外，麻醉剂还可以干扰脑发育过程中的突触发生。本研究的目的是通过评估挥发性麻醉剂对16日龄大鼠神经元细胞结构的暴露时间依赖性影响来探讨这一问题，16日龄大鼠是一个发育阶段，其特征在于大脑皮层中强烈的突触发生。Whistar大鼠接受异氟醚（1.5%），七氟烷（2.5%）或地氟烷（7%）麻醉30、60和120分钟，并在麻醉开始后6小时评价这些处理对神经元细胞结构的影响。使用Fluoro-Jade B染色和末端脱氧核苷酸转移酶脱氧尿苷三磷酸缺口末端标记测定来评估细胞死亡。离子电泳注射到第5层锥体神经元在内侧前额叶皮层允许可视化的树突状乔木。跟踪树突树进行了使用Neurolucida站（Microbrightfield，Williston，VT），而树突棘进行了分析，使用共聚焦microscopic.Results：长达2小时的曝光，没有挥发性药物诱导神经元细胞死亡或显着变化的毛树突乔木模式的第5层锥体神经元在出生后第16天的小狗。相反，这些药物显著增加了这些细胞树突轴上的树突棘密度。重要的是，这三个挥发性药物之间的显着差异被发现在暴露时间依赖性的影响树突棘density.Conclusion：这些新的结果表明，挥发性麻醉剂，具有不同的效力，而不诱导细胞死亡，可以迅速干扰突触发生的生理模式，从而可能会损害适当的电路组装在发育中的大脑皮层。
Background: Recent experimental observations suggest that, in addition to induce neuroapoptosis, anesthetics can also interfere with synaptogenesis during brain development. The aim of this study was to pursue this issue by evaluating the exposure time-dependent effects of volatile anesthetics on neuronal cytoarchitecture in 16-day-old rats, a developmental stage characterized by intense synaptogenesis in the cerebral cortex.Methods: Whistar rats underwent isoflurane (1.5%), sevoflurane (2.5%), or desflurane (7%) anesthesia for 30, 60, and 120 min at postnatal day 16, and the effect of these treatments on neuronal cytoarchitecture was evaluated 6 h after the initiation of anesthesia. Cell death was assessed using Fluoro-Jade B staining and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling assay. Ionotophoretic injections into layer 5 pyramidal neurons in the medial prefrontal cortex allowed visualization of dendritic arbor. Tracing of dendritic tree was carried out using the Neurolucida station (Microbrightfield, Williston, VT), whereas dendritic spines were analyzed using confocal microscopy.Results: Up to a 2-h-long exposure, none of the volatile drugs induced neuronal cell death or significant changes in gross dendritic arbor pattern of layer 5 pyramidal neurons in pups at postnatal day 16. In contrast, these drugs significantly increased dendritic spine density on dendritic shafts of these cells. Importantly, considerable differences were found between these three volatile agents in terms of exposure time-dependent effects on dendritic spine density.Conclusion: These new results suggest that volatile anesthetics, with different potencies and without inducing cell death, could rapidly interfere with physiologic patterns of synaptogenesis and thus might impair appropriate circuit assembly in the developing cerebral cortex.