Petroff O A, Rothman D L, Behar K L, Mattson R H
Department of Neurology, Yale University, New Haven, CT 06510, USA.
Neurology. 1996 May;46(5):1459-63. doi: 10.1212/wnl.46.5.1459.
Using 1H spectroscopy, we measured occipital lobe GABA levels serially in 18 patients enrolled in an ongoing open label trial of vigabatrin. Brain GABA levels were elevated twofold in patients taking vigabatrin (3 to 4 g/d) compared with nonepileptic subjects. Serial measurements suggested that brain GABA rose in proportion to vigabatrin dose up to 3 g/d. Doubling the dose from 3 to 6 g/d failed to increase brain GABA further. Serial measurements on three patients taking 6 g/d showed a gradual decrease in brain GABA in two patients over 1 to 2 years of treatment. These observations suggest that GABA synthesis may decrease at high GABA levels.
我们使用氢质子磁共振波谱技术，对18名正在参与一项关于氨己烯酸的开放标签试验的患者的枕叶γ-氨基丁酸（GABA）水平进行了连续测量。与非癫痫受试者相比，服用氨己烯酸（3至4克/天）的患者脑内GABA水平升高了两倍。连续测量结果表明，在氨己烯酸剂量达到3克/天之前，脑内GABA水平随剂量成比例上升。将剂量从3克/天加倍至6克/天未能进一步提高脑内GABA水平。对三名服用6克/天的患者进行的连续测量显示，在1至2年的治疗过程中，两名患者的脑内GABA水平逐渐下降。这些观察结果表明，在高GABA水平时，GABA合成可能会减少。
