本研究以不同類型的瑞特氏症模式小鼠進行藥物處理，來探討不同藥物對於運 動障礙的療效。結果發現，Mecp2 基因剔除公鼠在以管餵方式給予七天的厚朴生藥 後，可有效加快其在平衡桿上行走的速度並縮短到達標的的時間，而 Mecp2 條件缺 失公鼠在給予厚朴生藥後，由加速滾輪上掉落的延宕時間也有延長的趨勢。除此之 外，投予和厚朴酚合成純化物 (MH101)，可使 Mecp2 條件缺失母鼠之運動學習障 礙改善至與控制組鼠相似的表現 (如表二)。綜合以上結果顯示，厚朴生藥與和厚朴 酚合成純化物在不同瑞特氏症模式小鼠可有改善運動協調與運動學習障礙的效果。
除此之外，我們也利用 cFos 蛋白的偵測來檢視是否這些藥物的處理會改變神經細 胞的活性。結果發現，施打 MH101 之非條件缺失母鼠，其前腦前端內背側紋狀體 中表現 cFos 的神經細胞數目較控制組顯著的增加; 而 Mecp2 條件缺失母鼠在施打 MH101 後，前端內背側紋狀體的 cFos 神經元也較控制組有增加的趨勢。此結果顯 示 MH101 對 Mecp2 條件缺失母鼠運動學習能力的改善效果，有可能是因為增加了 前端內背側紋狀體的神經活性。最後，以植入式給藥膠囊與腦內注射導管直接給予 前端紋狀體μ 型類鴉片受體促效劑或第二型多巴胺受體拮抗劑，可有效防止野生型 小鼠在手術後初期的運動活力低下。
本研究對於瑞特氏症模式小鼠的運動障礙，提供了可能的藥物療癒方式 (
GABAA受體促效劑;
μ 型類鴉片受體促效劑;
第二型多巴胺受體拮抗劑) 與 關鍵的藥物作用腦區 (前端紋狀體)，未來可望應用於臨床上開發有效的治療策略。55
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VIII
附錄
附錄圖一 : 本研究所使用基因轉殖鼠之基因型鑑定。(A) Mecp2 基因剔除小鼠基因 型之凝膠電泳圖。(B) Mecp2T158A點突變小鼠基因型之凝膠電泳圖。(C) Dlx5/6-cre 基因轉殖鼠基因型之凝膠電泳圖 。(D) Flox-Mecp2 基因轉殖鼠基因型之凝膠電泳 圖。
IX
附錄圖二 : 基因轉殖鼠給予厚朴生藥期間體重之改變。(A)一個月大 Mecp2 基因剔 除公鼠於給藥十四天期間之體重改變。(B)一個月大 Mecp2T158A公鼠於給藥七天期 間之體重改變。(C) 一個月大 Mecp2 條件缺失公鼠於給藥七天期間之體重改變。(D) 四個月大 Mecp2 條件缺失母鼠於給藥七天期間之體重改變。曲線圖以 mean ± SEM 表示。*, p < 0.05; **, p < 0.01, repeated-measured two-way ANOVA, Bonferroni
post hoc test。
X
附錄圖三 : 基因轉殖鼠給予和厚朴酚合成純化物期間體重之改變。(A) 一個月大
Mecp2
T158A公鼠於給藥五天期間各組之體重比較。(B) 四個月大 Mecp2 條件缺失 母鼠於給藥五天期間各組之體重比較。曲線圖以 mean ± SEM 表示。 各組以 Repeated-measured two-way ANOVA 進行統計分析，並未發現有顯著差異。XI
附錄圖四 : 野生型小鼠敞箱行為之習慣化測試。(A) 一個月大 C57BL/6J 野生型小 鼠在前測過後，分別在第五天或第十一天再次進行敞箱行為測驗。柱狀圖以 mean ± SEM 表示。 **, p < 0.01, repeated-measured two-way ANOVA, Bonferroni post hoc test。