Corticothalamic modulation during absence seizures in rats: A functional MRI assessment
Corticothalamic modulation during absence seizures in rats: A functional MRI assessment
复制标题
DOI：
10.1046/j.1528-1157.2003.61002.x
复制
发表时间：
2003-09-01
期刊：
影响因子：
5.6
通讯作者：
Ferris, CF
中科院分区：
文献类型：
--
作者：
Tenney, JR;Duong, TQ;Ferris, CF
目的：应用功能磁共振成像(FMRI)技术对清醒状态下失神惊厥动物模型的脑激活区进行研究。方法：在4.7特斯拉条件下，用T2加权回波平面成像技术测量脑内血氧水平依赖性功能磁共振成像(BOLD)。分别在失神发作诱导前、失神发作期间和失神发作后用γ-丁内酯(GBL；200 mg/kg，腹腔注射)进行BOLD成像。结果：在失神癫痫发作中，对棘波放电(SWD)的形成起关键作用的皮质丘脑回路显示出强烈的信号变化，这与相同动物的脑电记录一致。丘脑发生了以积极为主的大胆变化。感觉皮质和顶叶皮质显示出混合的正负大胆变化，而颞叶和运动皮质仅显示负大胆变化。结论：通过BOLD fMRI技术，我们展示了脑区的信号变化，这些变化已经通过电生理学实验显示，对于以失神发作为特征的SWD的产生和维持具有重要意义。这些结果证实了先前从损伤和电生理实验中发现的结果，并显示了在全意识啮齿动物中无创成像失神发作的技术可行性。
Purpose: Functional magnetic resonance imaging (fMRI) was used to identify areas of brain activation during absence seizures in an awake animal model.Methods: Blood-oxygenation-level-dependent (BOLD) fMRI in the brain was measured by using T-2*-weighted echo planar imaging at 4.7 Tesla. BOLD imaging was performed before, during, and after absence seizure induction by using gamma-butyrolactone (GBL; 200 mg/kg, intraperitoneal).Results: The corticothalamic circuitry, critical for spike-wave discharge (SWD) formation in absence seizure, showed robust BOLD signal changes after GBL administration, consistent with EEG recordings in the same animals. Predominantly positive BOLD changes occurred in the thalamus. Sensory and parietal cortices showed mixed positive and negative BOLD changes, whereas temporal and motor cortices showed only negative BOLD changes.Conclusions: With the BOLD fMRI technique, we demonstrated signal changes in brain areas that have been shown, with electrophysiology experiments, to be important for generating and maintaining the SWDs that characterize absence seizures. These results corroborate previous findings from lesion and electrophysiological experiments and show the technical feasibility of noninvasively imaging absence seizures in fully conscious rodents.