A sequential double-label 14C- and 3H-2-DG technique: validation by double-dissociation of functional states.
A sequential double-label 14C- and 3H-2-DG technique: validation by double-dissociation of functional states.
复制标题
连续双标记 14C- 和 3H-2-DG 技术：通过功能状态的双解离进行验证。
DOI：
10.1007/bf00270687
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发表时间：
1987
影响因子：
2
通讯作者：
Goldman-Rakic,PS
中科院分区：
文献类型：
--
作者：
Friedman,HR;Bruce,CJ;Goldman-Rakic,PS
我们研究了一种双标记2-DG方案和分析方法，其中连续注射3 H-和14 C-2-DG用于绘制同一动物在两种不同实验治疗期间的脑代谢。在最初的研究中，仅给予3 H-2-DG或仅给予14 C-2-DG的大鼠的脑切片暴露在Ultrofilm和X射线胶片上，并插入一层聚酯薄膜（X射线/聚酯薄膜）。这些研究需要确定在50 ∶ 13 H ∶ 14 C剂量比下，3 H-2-DG摄取是否仅在Ultrofilm图像中显示，而14 C-2-DG摄取是否仅在X线/聚酯薄膜图像中显示。我们发现X射线/聚酯薄膜图像确实显示只有14 C-2-DG吸收，因为3 H发射被薄膜和聚酯薄膜的保护涂层阻挡。相比之下，Ultrofilm放射自显影显示14 C-2-DG和3 H-2-DG病例的2-DG摄取模式。然后，我们检查了双标记病例的放射自显影，其中14 C-2-DG和3 H-2-DG以100 ∶ 13 H ∶ 14 C的剂量比顺序给予，每次注射后进行不同的治疗。正如单标记病例所预测的，X线/聚酯薄膜图像中的活性对应于14 C-2-DG注射后的治疗，而Ultrofilm图像反映了两种治疗，因此不是3 H标记的真实表示。本文提供了一种解决14 C标记物污染Ultrofilm的方法，我们设计了一种使用计算机成像系统的减影算法，该算法从Ultrofilm图像中去除污染的14 C，留下3 H-2-DG摄取的“差异”图像。差异图像显示活性与3 H-2-DG注射后的处理一致。因此，X射线/聚酯薄膜和差异图像分别索引同一受试者中两种不同功能状态的代谢活动。通过允许受试者作为其自身的对照，这种双标记方法大大增加了2-DG方法的适用性和功效。
We investigated a double-label 2-DG protocol and method of analysis in which sequential injections of3H- and14C-2-DG were used to map brain metabolism during two distinct experimental treatments in the same animal. In initial studies, brain sections from rats given only3H-2-DG or only14C-2-DG were exposed on Ultrofilm and on X-ray film with an interposed sheet of mylar (X-ray/mylar). These studies were needed to determine whether, at the 50 ∶ 13H ∶14C dose ratio used,3H-2-DG uptake would be revealed only in Ultrofilm images and14C-2-DG uptake only in X-ray/mylar images. We found that X-ray/mylar images indeed showed only14C-2-DG uptake as3H emissions were blocked by the protective coating of the film and the mylar. By contrast, Ultrofilm autoradiograms showed the 2-DG uptake pattern for both the14C-2-DG and3H-2-DG cases. We then examined autoradiograms from double-label cases in which14C-2-DG and3H-2-DG were sequentially given using a 100 ∶ 13H ∶14C dose ratio, with a different treatment following each injection. As predicted from the single-label cases, activity in the X-ray/mylar images corresponded to the treatment that followed the14C-2-DG injection, while the Ultrofilm images reflected both treatments and thus were not veridical representations of3H label. This paper provides a solution to the contamination of Ultrofilm by14C label in that we devised a subtraction algorithm using a computerized imaging system which removes the contaminating14C from the Ultrofilm image, leaving a ‘Difference’ image of3H-2-DG uptake. Difference images revealed activity consistent with the treatment that followed the3H-2-DG injection. Thus, the X-ray/mylar and difference images separately indexed metabolic activity for two different functional states in the same subject. By allowing a subject to serve as its own control, this double-label method greatly increases the applicability and power of the 2-DG method.