Tissue Na, K, and Ca changes in regional cerebral ischemia: their measurement and interpretation.
Tissue Na, K, and Ca changes in regional cerebral ischemia: their measurement and interpretation.
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局部脑缺血中组织 Na、K 和 Ca 的变化：测量和解释。
DOI：
10.1089/cns.1986.3.215
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Cornu,P
中科院分区：
文献类型：
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作者：
Young,W;DeCrescito,V;Flamm,ES;Hadani,M;Rappaport,H;Cornu,P
描述了一种简单可靠的定量组织损伤的方法。这种方法的基础上，原子吸收光谱法测定钠，钾，钙浓度在小的大脑样品，适用于大鼠大脑中动脉闭塞模型（MCAo）。在梗塞部位，到24小时，Na浓度增加一倍以上，Ca浓度增加> 70%，K浓度下降近80%;这些变化与>80%的细胞破坏一致。一个显着的加速离子位移发生在4和6小时后MCAo。在4小时时，仅发生了24小时时发现的20-30%的离子位移;到6小时时，发生了24小时时发现的80-100%的离子位移。由于测量值反映了进出组织的离子运动，因此它们可能代表不可逆的组织损伤。虽然血脑屏障的破坏可能导致了离子位移速率的增加，但在4-6小时时，细胞外间隙和血管室之间必须存在大的离子梯度，以驱动离子位移。我们的研究结果表明，在大鼠MCAo模型中，治疗急性缺血性组织损伤的时间上限为4小时。所描述的方法和分析方法可能有助于确定急性CNS损伤治疗干预的时间窗，以及评估治疗效果。
A simple and reliable method of quantifying tissue damage is described. This method, based on atomic absorption spectroscopic determinations of Na, K, and Ca concentrations in small brain samples, was applied to the rat middle cerebral artery occlusion model (MCAo). At the infarct site by 24 hours, Na concentration more than doubled, Ca concentration increased by >70%, and K concentration fell nearly 80%; these changes are consistent with a >80% disruption of cells. A remarkable acceleration of ionic shifts occurred between 4 and 6 hours after MCAo. At 4 hours, only 20-30% of the ionic shifts found at 24 hours had occurred; by 6 hours, 80-100% of the ionic shifts found at 24 hours had taken place. Since the measurements reflect ionic movement into and out of the tissue, they are likely to represent irreversible tissue damage. Although blood brain barrier breakdown may have contributed to an increased rate of ionic shifts, large ionic gradients must have been present between the extracellular space and the vascular compartment at 4-6 hours to drive the ionic shifts. Our results suggest an upper time limit of 4 hours for treatments of acute ischemic tissue damage in the rat MCAo model. The methods and analytical approach described may be useful for determining the time window for therapeutic intervention in acute CNS injuries, as well as for evaluating treatment effects.