Development of an intracerebral glioma model in whole body irradiated hairless rats

Aims: To study the in vivo radiosensitivity of malignant gliomas, an animal glioma model was developed using the implantation of glioina cell lines in to the brain of the Hairless rat (a mutant from the Sprague-Dawley strain, characterised by its complete absence of hair). Methods: 10(6) malignant ce lls were suspended in 10 mu l phosphate buffered saline (PBS) and injected at a 4 mu m depth into the left frontal lobe of an anaesthetised animal thr ough a small craniotomy hole without opening the dura mater. The glioma cel l line C6 (abtained from a chemically-induced rat glioblastoma) was introdu ced into 11 animals, and the human glioblastoma line G5 into 12 animals. Re sults: The tumour take was checked using histological criteria. It was poor : 0% for the G5 line and only 27.3% for the C6 line. To improve the tumour growth rate, rats were subjected to a single dose (3.5 Gray) total body irr adiation, 24 hours prior to injection causing a marked immunosuppression. 8 4.6% of the mts grafted with the C6 line then produced tumours. Similar res ults (75% tumour take) were obtained using a stereotactic inoculation of th e tumour cells. Conclusions: Thanks to the contribution of whole body irrad iation an animal intracerebral glioma model was establish, which can be use d for clinical and biological studies.