微柱高效液相色谱法测定大鼠脑微透析液中 的乙酰胆碱和胆碱

用所建立的微柱高效液相色谱分离、柱后固定化酶反应器酶解、电化学检测器检测的方法, 对用不同浓度异氟醚麻醉前后的大鼠脑微透析液中的乙酰胆碱和胆碱的浓度进行了测定。在 乙酰胆碱和胆碱的浓度为10～ 2 000 nmol/L 时,其浓度分别与各自相应峰高的线性 关系良好,两者的检测限(以信噪比为3计)均可达5 nmol/L 。微透析液中乙酰胆碱和胆碱的含量在大鼠清醒时最高,随着异氟醚吸入浓度的增加,乙酰胆碱和胆碱含量明显降低。在大鼠海马和脑皮层中乙酰胆碱浓度的降低与大鼠吸入异氟醚的浓度相关( P ＜

Microbore High Performance Liquid Chromatographic Method for Measuring Acetylcholine and Choline in Microdialysates from Rat Brain

Acetylcholine (Ach) and choline (Ch), two important neurotransmitters, in vivo microdialysates obtained from hippocampus and frontal cortex of rats were measured by microbore high performance liquid chromatography with electrochemical detection combined with a post-column immobilized enzyme reactor. Good linear relationships (r~2=0.990 and 0.991) between the concentration (10-2 000 nmol/L) of Ach and Ch injected onto the column and peak height were found. The levels of Ach and Ch were found the highest during the period of wakefulness, and became increasingly lower during anesthetized periods due to the increased concentrations of inhaled isoflurane. Good correlation between the decrease in concentration of Ach in hippocampus and frontal cortex of rats and the concentration of inhaled isoflurane was found (P<0.05). The results indicate that isoflurane induced a dose-dependent decrease in concentration of Ach in the rat hippocampus and frontal cortex.