23例局灶腦皮質(zhì)發(fā)育不良性癲癇患者GAD-65/67的表達(dá)分布

饒英華 張訓(xùn) 秦明筠

[摘要]目的 探索局灶腦皮質(zhì)發(fā)育不良（FCD）性癲癇病灶中GAD-65/67表達(dá)分布情況。方法 收集廣州醫(yī)科大學(xué)附屬腦科醫(yī)院和廣州醫(yī)科大學(xué)附屬第二醫(yī)院2017年10月～2019年10月手術(shù)中切除的病灶標(biāo)本，23例FCD癲癇患者手術(shù)切除病灶為實驗組，7例無癲癇發(fā)作正常腦組織為對照組，運用免疫組化染色方法，觀察GAD-65/67的表達(dá)分布，利用電子顯微鏡對免疫組化載玻片進行拍照，用IEE 7.0軟件進行圖像色差分析。結(jié)果 實驗組、對照組均可見GAD-65/67表達(dá)分布，對照組腦組織觀測到GAD-65/67均勻分布于神經(jīng)纖維及突觸，實驗組病理組織學(xué)觀察到神經(jīng)元形態(tài)異常、排列紊亂，GAD-65/67表達(dá)分布相應(yīng)發(fā)生改變。結(jié)論 FCD由于發(fā)生大腦皮層發(fā)育異常，GAD-65/67分布異常，可能是導(dǎo)致γ-氨基丁酸的抑制功能減弱的重要原因。

[關(guān)鍵詞]局灶腦皮質(zhì)發(fā)育不良;GAD-65/67;癲癇;免疫組化

[中圖分類號] R742.1 ? ? ? ? ?[文獻(xiàn)標(biāo)識碼] A ? ? ? ? ?[文章編號] 1674-4721（2020）8（c）-0102-04

[Abstract] Objective To explore the expression and distribution of GAD-65/67 in patients with ?forcal cortical dysplasia （FCD） epilepsy. Methods Surgical focus specimen of inpatients were collected from the Affiliated Brain Hospital of Guangzhou Medical University and the Affiliated Second Hospital of Guangzhou Medical University from October 2017 to October 2019. The expression of GAD-65/67 was observed by immunohistochemical staining in 23 patients with FCD epilepsy who underwent surgical resection （the experimental group） and 7 normal brain tissues without epilepsy （the control group）. All the stained sections were examined under a microscope and photographed with a digital camera and the image chromatic aberration was analyzed by IEE 7.0 software. Results The expression of GAD-65/67 was found in both the experimental group and the control group. In the control group， GAD-65/67 was found to be evenly distributed in nerve fibers and synapses in brain tissue. In the experimental group， abnormal morphology and arrangement of neurons were observed and the expression and distribution of GAD-65/67 were changed correspondingly. Conclusion This study suggests that the abnormal distribution of GAD-65/67 may be attributed to the abnormal development of cerebral cortex in FCD， resulting in the decrease of GABA inhibition.

[Key words] Focal cortical dysplasia; GAD-65/67; Epilepsy; Immunohistochemistry

癲癇是常見的神經(jīng)系統(tǒng)疾病，嚴(yán)重影響患者的生活質(zhì)量，其中局灶腦皮質(zhì)發(fā)育不良（FCD）是難治性癲癇的重要原因之一，其確切的發(fā)病機制仍不清楚，內(nèi)科治療及外科手術(shù)仍難以控制癲癇發(fā)作[1-2]。有學(xué)者認(rèn)為，癲癇是由大腦皮層神經(jīng)網(wǎng)絡(luò)興奮性和抑制性因素之間的不平衡引起的過度興奮現(xiàn)象，再加上大量神經(jīng)元群體中的強烈同步放電所引起[3]，γ-氨基丁酸（GABA）是重要的中樞抑制性遞質(zhì)，分布于神經(jīng)軸突和小神經(jīng)元，GABA由谷氨酰胺通過谷氨酸脫羧酶（GAD）的催化下合成，GAD是GABA的限速酶，GAD存在GAD65和GAD67兩種同工酶[4]。目前有研究表明GABA與癲癇、焦慮癥、精神分裂癥、僵硬綜合癥等疾病相關(guān)[5-6]。本研究擬通過FCD癲癇患者病灶處GAD-65/67的表達(dá)分布情況探討FCD相關(guān)性癲癇的發(fā)病機制，現(xiàn)報道如下。

1資料與方法

1.1一般資料

收集廣州醫(yī)科大學(xué)附屬腦科醫(yī)院神經(jīng)外科和廣州醫(yī)科大學(xué)附屬第二醫(yī)院癲癇中心2017年10月～2019年10月收治的FCD相關(guān)難治性癲癇患者手術(shù)中切除的病灶，運用磁共振、PET/CT、視頻腦電圖等進行術(shù)前評估和定位，術(shù)中腦電圖定位切除病灶，術(shù)后病理診斷參考國際抗癲癇聯(lián)盟的FCD診斷標(biāo)準(zhǔn)[7]，共納入FCD患者23例為實驗組，其中ⅠA型4例，ⅠB型5例，ⅡA型6例，ⅡB型8例;女10例，男13例;年齡2～35歲，平均（11.6±4.6）歲。對照組7例，為無癲癇相關(guān)病史的正常腦皮層組織，為術(shù)中大腦皮層造瘺獲取，女3例，男4例，年齡5～68歲，中位年齡35歲。

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（收稿日期：2020-03-30）