心肌梗塞是一種急性的心臟疾病，其最常見的成因為冠狀狹窄或阻塞，心肌細胞無法透過冠狀動脈獲得足夠的氧氣和養分而壞死。在心肌梗塞的區域中，壞死的心肌細胞會逐漸形成纖維化的成疤組織(scar tissue)。取而代之的纖維化組織缺乏正常心肌細胞中電訊號傳遞的功能，進而導致心律不整甚至心臟功能的喪失。在本論文中，我們將導電性高分子聚3-氨基-4-甲氧基苯甲酸(poly-3-mino-4-methoxybenzoic acid, PAMB)接枝於明膠(gelatin)上並利用1-乙基-(3-二甲基氨基丙基)碳酰二亞胺鹽酸鹽(1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, EDC)搭配N-羥基琥珀醯亞胺(n-hydroxysuccinimide, NHS)交聯製備出具生物相容性的自我摻雜導電性水膠(Gel-PAMB)，期望將材料注射於心臟梗塞患部幫助心肌電訊號的傳遞，使心臟同步收縮，達到心臟功能恢復之目的。在體外實驗裡，我們分別以鈣離子指示劑Ca2+ indicator及微電極陣列證實了自我摻雜導電性水膠Gel-PAMB具有協助心肌細胞的電訊號耦合及電訊號傳遞能力。而在動物實驗裡，我們以外科手術方式將大鼠冠狀動脈結紮，建立心肌梗塞的模型後，將開發的導電性水膠注射至纖維化的成疤組織周圍，並使用心電圖、光學影像映射系統、心臟超音波、體外微電極陣列等分析大鼠心臟功能的恢復。我們發現注射自我摻雜導電性水膠Gel-PAMB後能有效的恢復心臟功能，包括了心律不整現象的減輕、心臟電訊號傳遞速率上升及左心收縮力增強。由以上實驗結果可知，本論文所開發出的自我摻雜導電性水膠Gel-PAMB能有效地連接成疤組織處阻斷的心肌電訊號，進而同步心肌收縮，恢復心臟功能，具有應用於心肌梗塞疾病治療的潛能。

Myocardial infarction (MI) induces permanent loss of cardiomyocytes and forms fibrous scar tissues. The nonconductive nature of fibrous scar tissues can cause desynchronized cardiac contraction, owing to the electrically uncoupling viable cardiomyocytes in the infarct region. In this work, a self-doping conductive polymeric hydrogel (Gel-PAMB) was synthesized by grafting the conductive poly-3-amino-4- methoxybenzoic acid (PAMB) on biocompatible gelatin (Gel) and then crosslinked by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) in combination with N-hydroxysuccinimide (NHS), which can be injected to the MI tissues to support electric conduction, thus improving cardiac function. The results of the in vitro study demonstrated that Gel-PAMB enhanced electrical signaling propagation and electrical coupling between cardiomyocytes, as confirmed through the calcium signaling analysis and microelectrode arrays. Furthermore, The Gel-PAMB was injected into the MI area of rats, and the preliminary in vivo experiments showed that a significant improvement of heart functions, such as reduced spontaneous arrhythmia, improved conduction velocity, and increased fractional shortening, was achieved as compared to Gel treatment. Overall, both in vitro and in vivo results clearly suggests that the Gel-PAMB can synchronize cardiac contraction by electrically bridging isolated viable cardiomyocytes within the scar tissues, restoring the global heart function. The use of this novel injectable conductive hydrogel may provide a new therapy strategy for the treatment of MI.

摘要 Ⅰ
目錄 III
圖錄 V
第一章 緒論 1
1.1 心肌梗塞 1
1.2 心肌梗塞患部環境 1
1.3 導電性高分子 3
1.4 導電性高分子聚3-胺基-4-甲氧基苯甲酸(3-amino-4-methoxybenzoic acid, PAMB) 4
1.5 治療心肌梗塞所面臨的難題 5
1.6 自我摻雜導電性水膠 5
1.7 研究動機與實驗目的 5
第二章 材料與方法 8
2.1 製備自我摻雜導電性水膠Gel-PAMB 8
2.2 自我摻雜導電性水膠Gel-PAMB結構分析 8
2.3 自我摻雜導電性水膠Gel-PAMB自我摻雜特性分析 8
2.4 自我摻雜導電性水膠Gel-PAMB導電度分析 8
2.5 自我摻雜導電性水膠Gel-PAMB機械性質分析 9
2.6 自我摻雜導電性水膠Gel-PAMB流體性質分析 9
2.7 自我摻雜導電性水膠Gel-PAMB澎潤度量測 9
2.8 新生幼鼠心肌細胞的分離與培養 9
2.9 自我摻雜導電性水膠Gel-PAMB生物相容性之測試 10
2.10 評估心肌細胞於自我摻雜導電性水膠Gel-PAMB上的電訊號耦合 10
2.11 新生鼠心肌細胞於Gel-PAMB材料表面之電訊號傳遞分析 11
2.12 建立大鼠心肌梗塞動物模型並進行水膠注射 11
2.13 量測心臟成疤組織之心臟電位 11
2.14 分析離體大鼠心臟的電訊號耦合情形 11
2.15 心電圖量測 12
2.16 執行心臟超音波 12
第三章 實驗結果與討論 13
3.1 Gel-PAMB導電度測定 13
3.2 Gel-PAMB結構分析 14
3.3 Gel-PAMB自我摻雜特性 16
3.4 Gel-PAMB之交聯 16
3.5 Gel-PAMB彈性係數之分析 17
3.6 Gel-PAMB流體性質之分析 18
3.7 Gel-PAMB澎潤度之分析 19
3.8 Gel-PAMB生物相容性測試 20
3.9 新生鼠心肌細胞於Gel-PAMB上之電訊號傳遞分析 21
3.10 新生鼠心肌細胞之鈣離子訊號量測 23
3.11 心臟成疤組織處之電位量測 24
3.12 心臟電訊號傳遞量測 25
3.13 心電圖量測 26
3.14 左心室功能指標量測 27
第四章 結論 29
參考文獻 30

[1] Laflamme MA, Murry CE. Heart regeneration. Nature. 2011;473:326–35.
[2] Laflamme MA, Murry CE. Regenerating the heart. Nat Biotechnol. 2005;23:845–56.
[3] Heart Attack, American Heart Association, Retrieved November 23, 2015, from http://watchlearnlive.heart.org/CVML_Player.php?moduleSelect=hrta tk.
[4] Stuart SDF, De Jesus NM, Lindsey ML, Ripplinger CM. The crossroads of inflammation, fibrosis, and arrhythmia following myocardial infarction. J Mol Cell Cardiol. 2016;91:114-122
[5] Nahrendorf M, Pittet MJ, Swirski FK. Monocytes: protagonists of infarct inflammation and repair after myocardial infarction. Circulation. 2010;121(22):2437–45.
[6] Baum J, Long B, Cabo C, Duffy H. Myofibroblasts cause heterogeneous Cx43 reduction and are unlikely to be coupled to myocytes in the healing canine infarct. Am J Physiol Heart Circ Physiol. 2012;302(3):H790-H800.
[7] Awada HK, Hwang MTP, Wang YD. Towards comprehensive cardiac repair and regeneration after myocardial infarction: Aspects to consider and proteins to deliver. Biomaterials. 2015;82:94-112.
[8] Bichonhealth.org. Bichon Frise Club of America | Health Resource Center | Articles: Hereditary Canine Cardiac Diseases - Dilated Cardiomyopathy (DCM).
[9] Kaur G, Adhikari R, Cass P, Bown M, Gunatillake P. Electrically conductive polymers and composites for biomedical applications. Rsc Adv. 2015;5(47):37553-567.
[10] Guimarda NK, Gomezb N, Schmidt CE. Conducting polymers in biomedical engineering. Prog. Polym. Sci. 2007;32(8-9):876-921.
[11] Mihic A, Cui Z, Wu J, Vlacic G, Miyagi Y, Li S, et al. A Conductive polymer hydrogel supports cell electrical signaling and improves cardiac function after implantation into myocardial Infarct. Circulation. 2015;132(8):772-784.
[12] Wu YB, Wang L, Guo BL, Ma PX. Interwoven aligned conductive nanofiber yarn/hydrogel composite scaffolds for engineered 3D cardiac anisotropy. ACS Nano. 2017;11(6):5646-5659.
[13] Kim SC, Whitten J, Kumar J, Bruno FF, Samuelson LA. Self-doped carboxylated polyaniline: effect of hydrogen bonding on the doping of polymers. Macromol Res. 2009;17(9):631-637.
[14] Huang JH, Hu XY, Lu L, Ye Z, Zhang QY, Luo ZJ. Electrical regulation of Schwann cells using conductive polypyrrole/chitosan polymers. J Biomed Mater Res A. 2010;93A(1):164-174.
[15] Rivers TJ, Hudson TW, Schmidt CE. Synthesis of a novel, biodegradable electrically conducting polymer for biomedical applications. Adv Funct Mater. 2002;12(1):33–37.
[16] Hsiao CW, Bai MY, Chang Y, Chung MF, Lee TY, Wu CT, et al. Electrical coupling of isolated cardiomyocyte clusters grown on aligned conductive nanofibrous meshes for their synchronized beating. Biomaterials. 2013;34(4):1063–1072.
[17] Merino S, Martín C, Kostarelos K, Prato M, Vazquez E. Nanocomposite hydrogels: 3D polymer-nanoparticle synergies for on-demand drug delivery. ACS Nano. 2015;9(5):4686-97.
[18] Liang HC, Chang WH, Lin KJ, Sung HW. Genipin-crosslinked gelatin microspheres as a drug carrier for intramuscular administration: In vitro and in vivo studies. J Biomed Mater Res A. 2003;65A(2): 271-282.
[19] Bhana B, Iyer RK, Chen WLK, Zhao RG, Sider KL, Likhitpanichkul M, et al. Influence of substrate stiffness on the phenotype of heart cells. Biotechnol Bioeng. 2010;105(6):1148–1160.