桃紅四物湯併用血栓溶解劑(rt-PA)在大鼠自體凝血塊引發腦栓塞的實驗模式中，兩者之交互作用及降低蜘蛛膜下腔出血的影響

許準榕
台北醫學大學
腦血管中風是血管性疾病致死及發病的主要原因之ㄧ，影響人類健康甚鉅，但由於其突發性的關係，使得腦血管中風治療藥物的研發，一直沒有很大的進展；中藥傳統方劑在腦血管中風的臨床治療上已使用很久，然而其研究的完整性及科學性仍嫌不足。中醫臨床上無論對缺血性中風、出血性中風後遺症的病人，活血化瘀法為最常用的治療方法。中醫傳統活血化瘀方劑中，出自《醫宗金鑑》的桃紅四物湯，由桃仁、紅花、當歸、生地、赤芍、川芎、共6味中藥組成，其功效為逐瘀、養血、活血，多用於血瘀證的治療，且具極佳的功效，已為中醫臨床上廣泛使用的活血化瘀方劑之一。血栓溶解劑rt-PA為西醫臨床上治療缺血性腦中風最常用的藥物之一；研究指出及時給予rt-PA能夠使中風病人得到較好的治療效果；但因可能引起蜘蛛膜下腔出血(subarachidonic hemorrhage；SAH)的副作用，導致rt-PA的臨床應用備受限制。因此如何有效降低劑量、提高rt-PA的治療效果同時降低其副作用，為一值得深入研究的課題。本實驗室已證實桃紅四物湯(0.7 g/kg/day)能有效的降低缺血性腦中風約20% (圖一)，研究結果將刊載於國際知名的實證醫學期刊eCAM (Evidence-Based Complementary and Alternative Medicine 2011: 9; doi:10.1155/2011/803015)。上述實驗係使用矽膠栓子(embolus)來造成血管阻塞，此腦缺血中風動物模式其缺點為並不能完全符合臨床上中風病患的病理機制；本實驗室目前進一步發展能更符合實際臨床缺血性腦中風的實驗動物模式也就是利用大鼠自體的凝血塊 (blood clot)打入腦血管中引發腦栓塞(圖二)。因此我們希望在本計畫中，使用此實驗動物模式，進一步研究在桃紅四物湯固定劑量下(0.7 g/kg/day)併用不同劑量的血栓溶解劑rt-PA (12, 8, 4 mg/kg)，評估兩者對降低缺血性腦中風是否有加成作用，同時探討其相關的作用機轉；另外我們亦欲研究兩者併用是否亦能降低蜘蛛膜下腔出血的副作用。本年度計畫預計給予桃紅四物湯(0.7 g/kg/day)兩周後，對大鼠進行缺血性腦中風手術，並給予逐漸降低劑量的rt-PA(12, 8, 4 mg/kg)，測量其腦部缺血面積(infarct volume)的變化、神經缺陷引起行為變化的等級(neurologic examination)，以及是否會引起蜘蛛膜下腔出血的副作用；另外本計畫擬使用雷射都卜勒血流探測儀，評估桃紅四物湯併用rt-PA是否對腦血流的提升具有加乘的效應。另外我們也擬進一步分析其神經保護作用的機轉，如測量腦部組織相關的蛋白表現(與細胞凋亡、發炎有關的蛋白如MMP-9, caspases, HIF-1a, iNOS, TNF-a, VEGF, p-Akt, nitrotyrosine等)以及自由基(如OH.)的變化，藉此解開藥物可能的作用機轉。透過本研究計畫，相信能為桃紅四物湯在治療缺血性腦中風上，提出一個合理且科學化的依據，同時也為rt-PA在缺血性腦中風的應用上提供一個相輔的中藥來配合治療，相信對於有效的降低rt-PA的劑量以及減少其副作用的產生，具有重要的臨床意義。
關鍵字：缺血性腦中風，蜘蛛膜下腔出血，桃紅四物湯，血栓溶解劑

Studies the potentiation of Tao-Hong-Si-Wu-Tang and rt-PA in blood clot-induced ischemic stroke and lowering the side effect of subarachidonic hemorrhage

Joen-Rong Sheu
Taipei Medical University
Stroke, a leading cause of mortality and morbidity in the world. Although, our knowledge about the molecular and cellular pathophysiology of brain injury after focal ischemia, the development of new drugs intreating acute ischemia stroke has not progressed rapidly. Chinese medicine has long been considered as therapeutic value for stroke and heart attack. Although western medicine has arisen this view recently. To treat stroke, traditional Chinese medicical practitioners prescribe herbs that could open the blood vessels and promote the blood flow. Tao-Hong-Si-Wu-Tang, a Chinese formula, this dietary supplement used in treating ischemic stroke for a long time. Intravenous recombinant tissue plasminogen activator (rt-PA) remains the only ischemic stroke therapy which is established to improve clinical outcome. However, the use of this thrombolytic agent has been limited due to this deliver treatment within a narrow therapeutic time window, and the excess risk of brain hemorrhage and edema. Hence, it is important to develop strategies that could safely extend the therapeutic time window and limit the risk of brain hemorrhage for rt-PA, it could leads to increase the utilization of this effective treatment. In our previous study, we found that Tao-Hong-Si-Wu-Tang (0.7 g/kg/day) significantly reduced stroke approximately 20% (Evidence-Based Complementary and Alternative Medicine 2011: 9; doi:10.1155/2011/803015). In this project, we further investigate the synergic effect of Tao-Hong-Si-Wu-Tang and rt-PA in rat thromboembolic stroke. In this study, we fix the dose of Tao-Hong-Si-Wu-Tang (0.7 g/kg/day) associated with the reduced and in increased the dose of rt-PA (12, 8, and 4 mg/kg). On the other hand, we also evaluate the side effect of subarachidonic hemorrhage (SAH) in rats induced by the combination of Tao-Hong-Si-Wu-Tang (0.7 g/kg/day) and rt-PA (12, 8, and 4 mg/kg). Hemorrhage is to be quantified with grading system for SAH. The expressions of MMP-9, caspases, HIF-1a, iNOS, TNF-a, VEGF, p-Akt, nitrotyrosine and free radical (i.e., OH.) formation in brain tissues will be also assessed. Through this study, we will be understood the synergistic effect of Tao-Hong-Si-Wu-Tang and rt-PA in reducing ischemic stroke and further provide a rational basis of their regulatory mechanisms. The experimental design and results of this study will considerably be relevant in application of traditional Chinese medicine.
關鍵字：rt-PA；subarachnoid hemorrhage；thromboembolic stroke；Tao Hong Si Wu Tang