Regulation of the effect of anesthetics-relationships with intracerebral pharmacokinetics and adrenoceptors

探讨脑内肾上腺素能受体对局麻药中枢神经系统毒性的影响。在清醒大鼠模型中，脑内注射心得安，一种β肾上腺素能受体拮抗剂，显著提高了利多卡因诱发惊厥的阈值。采用微透析法测定脑细胞外液中局麻药浓度，以阐明局麻药从外周血向脑内的内流。我们发现，只有蛋白质非结合部分的局部麻醉剂扩散到大脑中。

Effect of intracerebral adrenoceptors on central nervous system toxicity of local anesthetics was investigated. In awake rat model, intracerebral administration of propranolol, a beta adrenoceptor antagonist, significantly increased the threshold for lidocaine-induced convulsions. For elucidating the influx of local anesthetics from peripheral blood to the brain, concentration of local anesthetics in the cerebral extracellular fluid by microdialysis method. We found that only protein-unbound fraction of local anesthetics diffuses into the brain.