MR Perfusion Weighted Imaging of Antiangiogenesis in Rat C6 Glioma after Treatment with Stereotatic Radiosurgery
10.3969/j.issn.1002-1671.2010.02.028
- VernacularTitle:立体定位放射治疗对大鼠C6胶质瘤抗血管生成的MR灌注研究
- Author:
Qingbo ZHANG
;
Yi ZHANG
;
Xiaoyuan FENG
- Publication Type:Journal Article
- Keywords:
glioma;
MR imaging,perfusion;
experiment,rat
- From:
Journal of Practical Radiology
2010;26(2):262-267
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the antiangiogenic effect of stereotatic radiosurgery (SRS) in rat C6 gliomas using MR perfusion imaging(PWI) technique. Methods Twenty rats implanted with C6 glioma cells in the brain were randomly assigned into group A (without any therapy) and group B which underwent SRS therapy 4 weeks after implantation. PWI was performed to measure the regional cerebral blood volume (rCBV) and regional cerebral blood flow (rCBF) in tumor's region before therapy in all rats and 1 week later in group B. PWI sequence was applied pre-and post--inhalation of a mixture of 10% CO_2 and 90% air. rCBV and rCBF were analyzed. PaCO_2 and blood PH values were monitored before and aftermixed gas inhalation. All the MRI examination were car-ried out at a 3.0T magnet. The rats were sacrificed after MRI examination. Microvessel density (MVD) and number of mature ves-sels (with muscle layer) were measured histologically using immunohistochemical staining for factorⅧ and smooth muscle actin (SMA). PWI data, and pathological results were analyzed statistically. Results The size of tumors in group B remarkably de-creased with obvious necrotic area in the center 1 week after SRS therapy. PH value decreased and PaCO_2 increased significantly af-ter mixed gas inhalation. Blood gas data changes in group B were not significantly different from that in group A. The rCBV and rCBF of tumor's core in group B declined greatly after SRS treatment. The necrotic area was dark in rCBV and rCBF maps, that suggested no blood supply in this region. After therapy, the changing rate of rCBV and rCBF pre-and post-inhalation of gas in group B was greater than those in group A. The MVD of tumors in group B after treatment was sta-tistically less than that in group A. The number of SMA positively stained vessels in group B was nearly equal to that in group A. The percentage of SMA(+)/MVD in group B was significantly higher than that in group A. Conclusion SRS can inhibit the angiogenesis of rat C6 glioma, however vessels with smooth muscle cells are insensitive to SRS.
