Scheyer R D, During M J, Spencer D D, Cramer J A, Mattson R H
Department of Neurology, Yale University School of Medicine, New Haven, CT.
Neurology. 1994 Aug;44(8):1469-72. doi: 10.1212/wnl.44.8.1469.
We report the first study of carbamazepine and carbamazepine-10,11-epoxide concentrations determined by using intracerebral microdialysis in three patients undergoing depth electrode studies for the evaluation of medically intractable epilepsy. Very small microdialysis catheters, affixed to and inserted with the depth electrodes, sampled drug concentration in the extracellular environment. We perfused artificial extracellular fluid continuously, and varied the perfusion rate to permit estimation of the absolute drug concentration in the extracellular space. Serum samples were obtained simultaneously. The relation between dialysate and extracellular concentration (recovery fraction) depended, in vivo but not in vitro, on the relative lipophilicity of the compounds, suggesting that diffusion of the drug within the brain is a major determinant of microdialysate drug concentration. When this is taken into account, the steady-state extracellular concentrations of these compounds closely mirror their unbound serum concentrations.
我们报告了首例对3名因评估药物难治性癫痫而接受深部电极研究的患者，采用脑内微透析法测定卡马西平和卡马西平 - 10,11 - 环氧化物浓度的研究。非常小的微透析导管与深部电极固定并一同插入，用于采集细胞外环境中的药物浓度。我们持续灌注人工细胞外液，并改变灌注速率以估算细胞外空间中的绝对药物浓度。同时采集血清样本。透析液与细胞外浓度之间的关系（回收率）在体内而非体外取决于化合物的相对亲脂性，这表明药物在脑内的扩散是微透析液药物浓度的主要决定因素。考虑到这一点，这些化合物的稳态细胞外浓度与其未结合的血清浓度密切反映。
