MRS Measurements of GABA in Temporal Lobe Epilepsy

描述（由申请人提供）：GABA作为哺乳动物大脑中的主要抑制性神经递质，其含量及其受体系统是许多抗癫痫药物的靶点。尽管Petroff及其同事已经研究了各种抗癫痫药物对远离癫痫发病区域的枕叶GABA水平的影响，但迄今为止关于颞叶癫痫患者癫痫发病区域GABA水平的信息很少。这些数据在很大程度上表明，与健康对照组相比，控制不良的患者大脑GABA水平降低，并且对各种抗癫痫药物有反应。相反，最近的初步微透析研究表明，硬化患者的ECF GABA高于非硬化患者(6)。此外，我们的初步数据显示，ECF GABA与海马NAA水平呈负相关（即NAA水平较低的患者中ECF GABA水平较高）。与对照组相比，癫痫区总GABA增加或减少的程度尚不清楚。同样，总GABA水平是否与癫痫发生地的GABA水平平行尚不清楚。显然，这些问题可能对我们理解导致癫痫发作焦点的致痫性活动的因素有重大影响，并提供可能有助于癫痫患者治疗管理的措施。因此，开发一种可靠的方法来测量颞叶癫痫患者的颞叶GABA将具有重要的意义。

DESCRIPTION (provided by applicant): As the primary inhibitory neurotransmitter in mammalian brain, GABA, its content and its receptor systems are the targets of a number of anti-epileptic drugs. Although Petroff and colleagues have studied the effects of various anti-epileptics on brain GABA levels in the occipital lobe, a site distant from the epileptogenic region, to date little information exists regarding GABA levels in the epileptogenic region of patients with temporal lobe epilepsy. This data has largely shown that brain GABA levels are decreased in patients with poor control in comparison to healthy controls and are responsive to a variety of anti-epileptic medications. Conversely, recent preliminary microdialysis studies have shown that ECF GABA is higher in patients with sclerosis as opposed to those without sclerosis (6). Additionally our preliminary data has shown a similar correlation with ECF GABA inversely correlated with hippocampal NAA levels (i.e higher ECF GABA levels are seen in patients with lower NAA levels. To what extent total GABA in the epileptogenic region is increased or decreased relative to control is unknown. Similarly it is unknown if total GABA levels in the epileptogenic parallel GABA levels distant from the seizure focus. Clearly these questions may have significant impact on our understanding of the factors leading to epileptogenic activity in the seizure focus and also provide measures that may aid in the therapeutic management of epilepsy patients. Therefore the development of robust methods for measuring GABA from the temporal lobe in patients with temporal lobe epilepsy would be of significant benefit.