Hovda D A, Villablanca J R
Department of Surgery, UCLA School of Medicine, Los Angeles, CA 90095-7039, USA.
Brain Res Dev Brain Res. 1998 Sep 10;110(1):39-50. doi: 10.1016/s0165-3806(98)00092-3.
In order to determine the degree and extent of changes in cerebral oxidative capacity following cerebral hemineodecortication, adult cats which had undergone surgery early postnatally (mean age: 11.4 days) or during adulthood were studied using cytochrome oxidase histochemistry. A total of 18 animals were employed and 50 brain regions were quantified bilaterally using optical densitometry. Although many subcortical regions exhibiting extensive degenerative features revealed lower levels of cytochrome oxidase (C.O.) activity, this reduction was relatively unremarkable compared to intact controls. Nevertheless, it was interesting that this decrease (down to 66-89%) of normal was more pronounced in neonatal-lesioned cats, reaching significance in a number of ipsilateral thalamic nuclei, compared to adult-lesioned animals (91-100% of normal), suggesting a contribution of glial cells to the density of C.O. staining in the latter cats. Regions of the brain spared from degeneration exhibited a bilateral increase in C.O. activity which may reflect the demands for energy to support the anatomical reorganization which is prevalent in these animals. Surprisingly, such increases were more robust within spared regions of the adult-lesioned brain, reaching significance in four ipsilateral and nine contralateral areas with the density of the reaction attaining levels over 125% of control. This may indicate different demands for oxidative metabolism in the adult-lesioned cats. These results enhance our understanding of the mechanism(s) underlying the greater extent of functional sparing or recovery in cats sustaining injury to the cerebral cortex early vs. late in life. In addition, the findings complement our previous companion report on glucose metabolism supporting the concept of energy compartmentalization, which reflects the dynamic interaction between anatomical and functional changes in this age-at-lesion model of recovery.
为了确定大脑半侧去皮质术后大脑氧化能力变化的程度和范围，我们使用细胞色素氧化酶组织化学方法对出生后早期（平均年龄：11.4天）或成年期接受手术的成年猫进行了研究。总共使用了18只动物，并使用光密度测定法对双侧50个脑区进行了定量分析。尽管许多表现出广泛退行性特征的皮质下区域显示细胞色素氧化酶（C.O.）活性水平较低，但与完整对照组相比，这种降低相对不明显。然而，有趣的是，与成年期损伤的动物（正常水平的91 - 100%）相比，新生期损伤的猫中这种降至正常水平的66 - 89%的降低在许多同侧丘脑核中更为明显，这表明神经胶质细胞对后一组猫中C.O.染色密度有贡献。未发生退变的脑区C.O.活性出现双侧增加，这可能反映了为支持这些动物中普遍存在的解剖学重组而对能量的需求。令人惊讶的是，这种增加在成年期损伤大脑的未发生退变区域更为显著，在四个同侧和九个对侧区域达到显著水平，反应密度达到对照水平的125%以上。这可能表明成年期损伤的猫对氧化代谢有不同的需求。这些结果增进了我们对幼年与成年期大脑皮质损伤的猫在功能保留或恢复程度上差异背后机制的理解。此外，这些发现补充了我们之前关于葡萄糖代谢的相关报告，支持了能量分隔的概念，这反映了在这个损伤年龄恢复模型中解剖学和功能变化之间的动态相互作用。
