首页 | 本学科首页   官方微博 | 高级检索  
     


The response to carbogen breathing in experimental tumour models monitored by gradient-recalled echo magnetic resonance imaging.
Authors:S. P. Robinson   L. M. Rodrigues   A. S. Ojugo   P. M. McSheehy   F. A. Howe     J. R. Griffiths
Affiliation:Division of Biochemistry, St George''s Hospital Medical School, London, UK.
Abstract:Gradient-recalled echo magnetic resonance imaging (GRE MRI), which gives information on blood flow and oxygenation changes (Robinson SP, Howe FA, Griffiths JR 1995, Int J Radiat Oncol Biol Phys 33: 855), was used to observe the responses of six rodent tumour models to carbogen breathing. In one transplanted rat tumour, the Morris hepatoma 9618a, and a chemically induced rat tumour, the MNU-induced mammary adenocarcinoma, there were marked image intensity increases, similar to those previously observed in the rat GH3 prolactinoma. In contrast, the rat Walker carcinosarcoma showed no response. In two mouse tumours, the RIF-1 fibrosarcoma and the human xenograft HT29, carbogen breathing induced a transient fall in signal intensity that reversed spontaneously within a few minutes. The rat GH3 prolactinoma was xenografted into nude mice, and an increase in image intensity was found in response to carbogen, suggesting that any effects that carbogen may have had on the host were not significant determinants of the tumour response. The increases in GRE image intensity of the MNU, H9618a and GH3 tumours during carbogen breathing are consistent with increases in tumour oxygenation and blood flow, whereas the responses of the RIF-1 and HT29 tumours may be the result of a transient steal effect followed by homeostatic correction.
Keywords:
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号