竹叶石膏汤、沙参麦冬汤及血府逐瘀汤对放射性食管损伤的防治作用及机制研究

Radiation esophagitis is the most common complication during the radiotherapy for lung carcinoma, esophageal cancer, or mediastinal neophasms. It may cause great pains to the patients and even discontinue the radiotherapy, which can influence the effects of treatment for the tumors. However, there's no effective measures to prevent radiation esophagitis yet. Through many years of clinical investigation, we summarized its basic pathogenesis as "toxic heat invasion, deficiency of both qi and yin, and the the disorder of stomach-qi", therefore made ideal effects on preventing and treating it with Zhuye Shigao Decotion. The experiment also showed that the prescription could obviously relieve the histopathological injuries and inflammatory changes, improve the daily food intake and prevent the lose of body weight dose-dependent.According to our years of clinical experience and references research, on the basis of previous study, we choose representative classic decoctions of treating radiation esophagitis and compare them using pathological and molecular biological methods as to investigate the effects of different decoctions on radiation-induced esophagus injury and the mechanism,establish the sound theory system of TCM to prevent and treat radiation esophagitis.

放射性食管炎是肺癌、食管癌以及纵隔肿瘤等胸部肿瘤放疗中最常见的并发症，目前尚无有效预防措施，我们用经方竹叶石膏汤防治本病取得了理想的临床疗效，动物实验也证实本方能明显减轻放射性食管炎大鼠的病理损伤及炎性改变，增加饮食量及减缓体重下降，且呈现良好的量效相关性；对竹叶石膏汤进行初步拆方研究，结果显示竹叶石膏汤全方效果最佳，其机制可能与抑制炎性因子释放有关。基于此，选择竹叶石膏汤与临床报道有效的经典方沙参麦冬汤及血府逐瘀汤进行横向比较，采用家兔一次性大剂量照射和多次小剂量照射两种动物模型，通过在体和离体实验，结合病理学和分子生物学方法观察和评价不同方剂防治放射性食管损伤的效果，探讨不同方剂对不同模型的作用特点、最佳起效时间，并通过以方测证的方法阐明放射性食管损伤的中医证候学特点，为中医药防治放射性食管损伤构建较系统的理论体系，找到最佳防治方法及中药，并初步探讨其分子生物学机制及中药的作用机制。

目的：观察竹叶石膏汤与沙参麦冬汤、血府逐瘀汤防治家兔急性放射性食管损伤的效果，研究其作用机制。.方法：经过预实验最终选择了复方竹叶石膏颗粒代替竹叶石膏汤作为研究对象与临床报道有效的代表性经典方沙参麦冬汤及血府逐瘀汤进行横向比较，并建立了家兔一次性大剂量照射和多次小剂量照射两种动物模型，运用在体和离体试验，病理学和分子生物学方法（比色法，流式细胞分析，RT-PCR,WB）观察和评价不同方剂防治放射性食管损伤的效果，探讨不同方剂对不同模型的作用特点、最佳起效时间。.结果：复方竹叶石膏颗粒、血府逐瘀汤及沙参麦冬汤均可有效减轻食管放射损伤，其作用机制可能为降低氧自由基水平，提高抗氧化酶活性来减轻氧化损伤，也可上调Bcl-2、抑制Bax的表达来抑制细胞凋亡，其中复方竹叶石膏颗粒效果优于沙参麦冬汤与血府逐瘀汤，而沙参麦冬汤与血府逐瘀汤在防治方面并无显著差异。.结论：在放射性食管炎发展过程中，阴虚内热与瘀血内阻两种病机同时存在，沙参麦冬汤与血府逐瘀汤各为养阴清热法与活血化瘀法的代表方，二者作用机理不同，在临床上单用一种方法效果较为局限，复方竹叶石膏颗粒兼有益气养阴、清热解毒、活血化瘀等功效，有效涵盖了放射性食管炎的各种病理因素，疗效更优。