McAdoo David J, Wu Ping
Department of Neurosciences and Cell Biology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-1043, United States.
Pharmacol Biochem Behav. 2008 Aug;90(2):282-96. doi: 10.1016/j.pbb.2008.03.001. Epub 2008 Mar 10.
Central nervous system (CNS) insults elevate endogenous toxins and alter levels of indicators of metabolic disorder. These contribute to neurotrauma, neurodegenerative diseases and chronic pain and are possible targets for pharmaceutical treatment. Microdialysis samples substances in the extracellular space for chemical analysis. It has demonstrated that toxic levels of glutamate are released and that toxic levels of the reactive species O(2)(-), H(2)O(2), HO. NO and HOONO are generated upon CNS injury. Agent administration by microdialysis can also help elucidate mechanisms of damage and protection, and to identify targets for clinical application. Microdialysis sampling indicates that circuits descending from the brain to the spinal cord transmit and modulate pain signals by releasing neurotransmitter amines and amino acids. Efforts are under way to develop microdialysis into a technique for intensive care monitoring and predicting outcomes of brain insults. Finally, microdialysis sampling has demonstrated in vivo elevation of glial cell line-derived neurotrophic factor following grafting of primed fetal human neural stem cells into brain-injured rats, the first in vivo demonstration of the release of a neurotrophic factor by grafted stem cells. This increased release correlated with significantly improved spatial learning and memory.
中枢神经系统（CNS）损伤会升高内源性毒素并改变代谢紊乱指标的水平。这些因素会导致神经创伤、神经退行性疾病和慢性疼痛，并且可能是药物治疗的靶点。微透析可对细胞外空间中的物质进行采样以进行化学分析。研究表明，中枢神经系统损伤时会释放毒性水平的谷氨酸，并且会产生活性物质O(2)(-)、H(2)O(2)、HO.、NO和HOONO的毒性水平。通过微透析给药还可以帮助阐明损伤和保护机制，并确定临床应用的靶点。微透析采样表明，从大脑下行至脊髓的神经回路通过释放神经递质胺和氨基酸来传递和调节疼痛信号。目前正在努力将微透析发展成为一种用于重症监护监测和预测脑损伤预后的技术。最后，微透析采样已证明，将经预处理的人胎儿神经干细胞移植到脑损伤大鼠体内后，胶质细胞源性神经营养因子在体内升高，这是首次在体内证明移植干细胞释放神经营养因子。这种释放增加与空间学习和记忆的显著改善相关。
