ENDOTHELIAL CELL CYCLE ANTIOXIDANTS AND RADIATION

血管内皮细胞(EC)是FREE的主要靶点 包括辐射在内的许多疾病中的自由基/氧化应激 毒性。当内皮损伤时，EC分裂修复 血管屏障。这种增殖性反应可能发生在 持续的自由基/氧化应激环境。我们假设 扩散中的欧共体有不同的释放能力 自由基/氧化剂应激取决于它们在DNA中的位置 合成的或细胞周期的。我们假设这些不同的 易感性的部分原因是抗氧化剂/游离的不同。 激进的防御机制。EC将从牛身上培养出来 动脉和照射(0-10Gy137Cs，伽马射线)。Cewll循环 分布将通过流式细胞术进行量化。欧委会将会是 通过离心洗脱在细胞周期中丰富/同步， 荧光激活的细胞分选和(~3H)胸腺嘧啶核苷自杀。 将评估细胞毒性、急性和增殖性细胞死亡。 根据贴壁细胞的数量，乳酸脱氢酶的释放 存活参数由菌落计数得出。超氧化物 歧化酶和过氧化氢酶活性加上 谷胱甘肽氧化还原循环(还原型(GSH)和氧化型谷胱甘肽， 谷胱甘肽过氧化物酶、谷胱甘肽 还原酶、谷胱甘肽合成酶、葡萄糖-6- 磷酸脱氢酶和6-磷酸葡萄糖脱氢酶) 将会被测量。天然水平的抗氧化剂防御系统将 与细胞周期位置和细胞毒性有关 照射后。然后防御将被封锁(DDTC，ATZ， 低硒培养液、BCNU、BSO和CDNB)。接下来，在 阻滞剂的存在和不存在，酶的活性将 用原封不动的聚乙二醇处理来提高 偶联或脂质体包裹的酶。的影响 这些变化对细胞毒性和细胞周期进程的影响 (通过流式细胞仪和放射自显影监测) 量过了。这些实验将阐明EC的作用机制。 销毁和扩散，并应有助于 心肺血管疾病的特效治疗进展 血管疾病。

Vascular endothelial cells (EC) are primary targets of free radical/oxidant stress in many diseases including radiation toxicity. When endothelium is injured, the EC divide to repair the vascular barrier. This proliferative response probably occurs in a milieu of sustained free radical/oxidant stress. We hypothesize that proliferating EC have different susceptibilities to freee radical/oxidant stress depending on their position in the DNA synthetic or cell cycle. We hypothesize that these different susceptibilities are due partly to variations in antioxidant/free radical defense mechanisms. EC will be cultured from bovine aorta and irradiated (0-10 Gy, 137 Cs, gamma rays). Cewll cycle distribution will be quantified by flow cytometry. The EC will be enriched/synchronized in cell cycle by centrifugal elutriation, fluorescence activated cell sorting and (3H) thymidine suicide. Cytotoxicity, acute and proliferative cell death, will be assessed by the number of adherent cells, release of lactate dehydrogenase and survival parameters derived from colony counts. Superoxide dismutase, and catalase activities plus components of the glutathione redox cycle (reduced (GSH) and oxidized glutathione, and the enzymatic activities of glutathione peroidase, glutathione reductase, glutathione synthetases, glucose-6- phosphodehydrogenase and 6-phosphogluconate dehydrogenase) will be measured. Innate levels of the antioxidant defenses will be related to cell cycle position and cytotoxicity both before and after irradiation. The defenses then will be blocked (DDTC, ATZ, selenium-deficient medium, BCNU, BSO and CDNB). Next, in the presence and absence of the blockers, the enzyme activities will be raised by treatments with unaltered, polyethylene glycol conjugated or liposome encapsulated enzymes. The effects of these alterations on cytotoxicity and cell cycle progression (monitored by flow cytometry and autoradiography) will be measured. These experiments will clarify mechanisms of EC destruction and proliferation and should help with the development of specific treatments for cardiopulmonary and vascular disease.