美***的Doccol线拴是脑缺血MCAO模型稳定的保证，可将脑梗塞体积标准差减少至5%，并避免蛛网膜下腔出血，不需要激光多普勒检测血流也能获得极为稳定的结果。Doccol线拴是***际脑缺血研究中应用***多的线拴，是Nature，Stroke，J Neurosci 等顶***杂志报道***多的线拴。同时，每只鼠MCAO的线栓成本***低仅为10-20元（可重复使用型号，视重复使用次数决定）。

                                Doccol MCAO线拴的选择

注：（1）型号的命名根据线号、外径、硅胶包被长度、一个包装中的线拴数量、是否可重复使用确定。如“701956PK5Re”为7号线，0.19mm外径，硅胶包被长度5-6mm，PK5一个包装中的数量是5根，Re可重复使用。（2）在美国，绝大多数的实验者都选用上表推荐的可重复使用型号，即所谓“starter kits”。（3）Re型号重复使用的次数，每位实验者差别很大，2-10次不等。

Doccol MCAO线拴可以将脑梗塞体积标准差减少至5%

      成功的MCAO模型的脑血流在插入线拴时会有断崖式下降；在拔出线拴后，激光多普勒检测的血流会很快恢复（图A）。采用硬质尼龙鱼线线拴，极易戳破血管，造成蛛网膜下腔出血（Subarachnoid hemorrhage，图B）。手术过程中血管如果被线拴戳破，脑血流不会有断崖式下降，而是缓慢下降；在拔出线拴后，脑血流也不会恢复。造成脑梗塞体积变异的原因还有，不完全的梗塞血管或线拴移位造成的血流下降程度不均***及提前灌注。因此，线栓的质地是MCAO模型稳定的关键。

   对于MCAO模型来说，主要有两种线拴，无包被的火焰熔烫圆头线拴及硅胶包被线拴。研究表明(Tsuchiya et al. 2003)，无包被的圆头线拴在MCAO实验过程中可能导致高达40%的蛛网膜下腔出血，而其标准差可能比平均值的50%还要大。另***项技术文章表明(Shimamura et al. 2006a)，硅胶包被线拴要远好于无包被的圆头线拴，其结果更为稳定，即使对于没有经验的实验者来说也是如此。而多聚赖氨酸包被的线拴只能增加死亡率，不能减少梗赛体积的变异程度(Huang et al. 1998)。

     Doccol MCAO线拴全部为硅胶包被，圆润、柔软、包被均匀，即使在没有激光多普勒实时检测的情况，也不会将血管戳破。使用自制的硅胶包被的线拴，大鼠(Schmid-Elsaesser et al. 1998)及小鼠(Shah et al. 2006)的脑梗塞体积的标准差均在30%左右。而使用Doccol MCAO线拴可以得到更好的结果。对于大鼠MCAO模型来说，使用Doccol MCAO线拴得到的结果的标准差可达10%-20% （Ruscher et al.2012；Ishizaka et al.2013；Sakata et al.2012；Candelario-Jalil et al. 2008；Khan et al. 2006；Liu et al. 2006；Shimamura et al. 2006b；Solaroglu et al. 2006；Tsubokawa et al. 2007；Tsubokawa et al. 2006a；Tsubokawa et al. 2006b)。对于小鼠来说，使用Doccol MCAO线拴得到的结果的标准差可达5%-10%(Chen et al.2014; Bae et al.2013; Jin et al.2011; Gu et al.2012; Kleinschnitz et al. 2007; Maysami et al. 2008; Pignataro et al. 2007b; Pignataro et al. 2007c)。

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