PHYSIOLOGICAL FACTORS IN HYPERTHERMIA

热疗的生理因素

• 批准号: 3186663
• 负责人: Chang Won Song
• 金额: $ 14.03万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-01-01 至 1990-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3186663
• 关键词: blood flow measurement; drug delivery systems; laboratory rat; neoplasm /cancer blood supply; neoplasm /cancer thermotherapy; nutrition aspect of cancer; thermostability

Hyperthermia used in combination with radiotherapy or chemotherapy is becoming an established modality for the treatment of cancer. Although malignant cells are not necessarily more heat-sensitive than normal cells, tumors are generally more vulnerable to heat than are normal tissues. It is believed that the intrinsic difference in the vascular structure as well as the thermal response of vasculature and related physiological and metabolic factors in tumors and normal tissues is the main cause of such preferential effect of hyperthermia on tumors. Specifically, the temperature in tumors tends to rise higher than that in adjacent normal tissues during heating, owing to the inefficient heat dissipation by the sluggish blood flow in the tumors relative to that in the normal tissues. It has been known that the thermosensitivity of mammalian cells is profoundly enhanced by acidic and poor nutritional conditions. Interestingly, the intratumor environment is acidic and nutritionally deprived. This condition is further enhanced in the heated tumor probably due to vascular function and related physiological and biochemical factors for the effective use of hyperthermia. The longterm objective of this sutdy is to further understand the role of blood flow and related microenvironment in the hyperthermic treatment of cancer. The specific aim of this application is to elucidate the heatinduced vascular changes in normal internal organs. The heatedinduced change in blood flow in cutaneous tissue has been extensively studied, but the effect of heat on the blood flow in other normal tissues, including the organs in the body cavity, is virtually unknown. This may be attributed to the fact that a suitable device to heat the deep internal organs has not been available. We recently acquired a capacitive heating device capable of heating deep internal organs of experimental animals. We propose to investigate the effect of heat on the blood flow and also determine the threshold thermal dose for vascular damage in various internal organs of rats. The blood flow will be measured with the radioactive microsphere method, which has long been established in our laboratory. We strongly believe the information obtained in this study will provide a rationale basis on which an effective use of hyperthermia to treat deepseated human tumors can be planned.

与放疗或 化学疗法正在成为一种已建立的方式 癌症的治疗。 尽管恶性细胞不是 比正常细胞比正常细胞更重要，肿瘤是 通常比正常组织更容易受到热量。 这是 认为血管结构的内在差异为 以及脉管系统和相关的热响应 肿瘤和正常组织的生理和代谢因子 是热疗对这种优先影响的主要原因 肿瘤。 具体而言，肿瘤的温度倾向于升高 加热过程中相邻的正常组织中的高度高 通过缓慢的血液流动到效率低下的热量耗散 肿瘤相对于正常组织中的肿瘤。 众所周知 哺乳动物细胞的热敏性是深刻的 通过酸性和营养条件不良增强。 有趣的是， 肿瘤内的环境是酸性的，营养被剥夺了。 这种情况可能在加热肿瘤中进一步增强 由于血管功能以及相关的生理和生化 有效使用热疗的因素。 长期 这个牢固的目的是进一步了解血液的作用 高温治疗中的流量和相关微环境 癌症。 本应用的具体目的是阐明 正常内脏的热诱导血管变化。 皮肤组织中加热诱导的血流变化已 经过广泛的研究，但是热量对血流的影响 在其他正常组织中，包括体腔中的器官， 几乎未知。 这可能归因于以下事实 适合加热深内器官的设备尚未 可用的。 我们最近获得了电容加热设备 能够加热实​​验动物的深内器官。 我们建议研究热量对血流的影响，并 还要确定阈值热剂量的血管损伤 大鼠的各种内部器官。 血流将测量 使用放射性微球法，长期以来一直是 在我们的实验室中建立。 我们坚信信息 在这项研究中获得的将提供一个理由基础 有效利用热疗治疗深度的人类肿瘤 可以计划。