Evaluation of 14C(11C)-Benzyl acetate as a potential probe for the measurement of glial metabolism.

为了评价[1-14C]乙酸苄酯([1-14C]BA)在体内测定胶质细胞氧化代谢的有效性，用解剖方法研究了小鼠和大鼠脑内注射示踪剂后的动力学。在注射示踪剂后，立即在小鼠和大鼠中看到了非常高的大脑摄取。脑组织中[1-14C]BA的放射性呈单指数曲线消失。[1-14C]BA的洗脱速率常数(K2)明显高于[2-14C]乙酸苄酯。K2值似乎是标记乙酸乙酯转化为标记二氧化碳的一个指标。通过使用简化的放射自显影，可以估计每个大脑感兴趣区域的K2值。以[1-11C]乙酰氯为原料合成了[1-11C]BA。使用麻醉或选择性神经胶质毒素预处理的清醒大鼠进行了[1-11C]BA的PET测量，但在未来的研究中还需要改进。

In order to evaluate the validity of benzyl [1-14C]acetate ([1-14C]BA) for in vivo measurement of glial oxidative metabolism, kinetics in the brain of mice or rats following injection of the tracer were studied by using the dissection method. Immediately after the tracer injection, a very high brain uptake was seen in mice and rats. Radioactivity of [1-14C]BA in the brain was disappeared as a single exponential curve. The washout rate constant (k2) of [1-14C]BA was considerably higher than that of benzyl [2-14C]acetate. The k2 value seems to be an index of conversion rate of labeled acetate to labeled CO2. By using simplified autoradiography, k2 value in each brain regions of interest could be estimated. [1-11C]BA was synthesized by using [1-11C]acetyl chloride. PET measurement of [1-11C]BA using anaesthetized or awake rats pretreated with selective glial toxin was performed, however several improvements are needed in future study.