[Therapeutic efficacy of intracarotid infusion of 20% mannitol with ACNU in Fischer rats with intracerebrally implanted 9L gliosarcoma]

Abstract

The purpose of this study was to investigate the therapeutic effect of intracarotid infusion of 20% mannitol with ACNU chemotherapy in Fischer 344 rats with intracerebrally implanted 9L gliosarcoma, compared with giving them only ACNU intraperitoneally. Thirty 9L gliosarcoma bearing Fischer 344 rats were evaluated in the following 3 groups. Group I: control (no treatment); group II: treated by ACNU 20 mg/kg intraperitoneally on the 7th day after implantation of 9L gliosarcoma cells; group III: treated by intracarotid infusion of 20% mannitol 3.1 ml/min. and with the same dose of ACNU as in group II. Mean survival time after the inoculation of tumor cells into the brain was 15.1 days (group I), 21.8 days (group II) and 27.9 days (group III). In group II all tumor-bearing Fischer rats died within 24 days after inoculation of tumor cells, whereas in group III 5 out of 6 rats survived more than 25 days after them. Group III evidenced necrosis and degenerative findings with vacuole and microcyst without vascular proliferation in tumor tissues more than group II on the 7th day after ACNU treatment for the experimental brain tumor. On the 7th day after ACNU treatment of each group, BrdU labeling index was calculated in order to evaluate tumor proliferation. The Mean BrdU labeling index in tumor cells of group III demonstrated 7.5%, against 14.5% (about one half) in group II. From our experimental study of survival time and BrdU labeling index, it is suggested that osmotic blood brain barrier disruption chemotherapy by intracarotid infusion of 20% mannitol and ACNU was more effective than simple treatment by intraperitoneal injection of ACNU in the Fischer rats with intracerebrally implanted 9L gliosarcoma.