Kimura H, Itoh S, Kawamura Y, Nakatsugawa S, Ishii Y
Department of Radiology, Fukui Medical School, Japan.
Magn Reson Imaging. 1994;12(1):109-19. doi: 10.1016/0730-725x(94)92358-2.
The bioenergetics of human lung tumors grown subcutaneously in KSN nude mice, were studied in vivo using 31P NMR spectroscopy up to 27 days following radiotherapy and/or hyperthermia. Six tumors were treated with radiation (20 Gy, single fraction) and hyperthermia (44 degrees C, 10 min). There was a significant increase in the ratio of inorganic phosphate to beta-nucleoside triphosphate (Pi/beta-NTP) 24 h after radiation plus hyperthermia (p < .01), but a significant decrease 6 days after the treatment (p < .05) relative to untreated controls. Furthermore, the combined therapy produce significant acidosis at 24 h post therapy followed by significant alkalosis at 6 days compared to no treatment. This biphasic pattern was also significant in comparison with the pretreatment values of Pi/beta-NTP and pH. The combined therapy produced not only tumor decline at 24 h indicated by increased Pi/beta-NTP ratio and acidic pH shift, but also metabolic activation of tumor cells at 6 days indicated by decreased Pi/beta-NTP ratio and alkalotic pH shift. The tumor blood flow estimated by hydrogen ion clearance curves were completely depleted at 24 h and fully recovered to pretreatment level at 6 days. Reasonable close negative correlation between the blood flow and Pi/beta-NTP ratio (r = -0.59, p < .01) indicated that the two contrasting physiological states were closely related to tumor perfusion status. The 31P spectra of tumors following the combined therapy were concluded to demonstrate additive physiological effects of hyperthermia and radiation.
利用³¹P核磁共振波谱技术，在体内研究了皮下接种于KSN裸鼠的人肺肿瘤在放疗和/或热疗后长达27天的生物能量学。六个肿瘤接受了放疗（20 Gy，单次分割）和热疗（44℃，10分钟）。放疗加 热疗后24小时，无机磷酸与β-核苷三磷酸的比率（Pi/β-NTP）显著增加（p < 0.01），但与未治疗的对照组相比，治疗后6天该比率显著降低（p < 0.05）。此外，与未治疗相比，联合治疗在治疗后24小时产生显著酸中毒，随后在6天时出现显著碱中毒。与Pi/β-NTP和pH的预处理值相比，这种双相模式也很显著。联合治疗不仅在24小时时导致肿瘤衰退，表现为Pi/β-NTP比率增加和酸性pH偏移，而且在6天时导致肿瘤细胞代谢激活，表现为Pi/β-NTP比率降低和碱性pH偏移。通过氢离子清除曲线估计的肿瘤血流在24小时时完全耗尽，在6天时完全恢复到预处理水平。血流与Pi/β-NTP比率之间存在合理的密切负相关（r = -0.59，p < 0.01），表明这两种相反的生理状态与肿瘤灌注状态密切相关。联合治疗后肿瘤的³¹P谱被认为显示了热疗和放疗的相加生理效应。
