AIM: To observe morphological changes in transplanted intracerebral rat gliomas and rat survival time with gliomas under chemotherapy with angiotensin II-induced hypertension. METHODS: C6 glioma cells were cultured, and the effects of carmustine, nimodipine or/and teniposide on gliomas cells was observed. In addition, the brain tumor model was established in Wistar rats by stereotaxic inoculation of C6 glioma cells. The tumor-bearing rats were treated with carmustine, nimodipine lisplatin or/and teniposide during angiotensin II-induced hypertension, the pathological changes in gliomas was also examined. RESULTS: In vitro experiments showed chemotherapy resulted in morphologic changes in glioma cells, including cell enlargement, degeneration. In vivo experiments, the survival time of tumor-bearing rats was longer, the voume of gliomas was smaller in chemotherapy with hypertension group than those in chemotherapy alone, and pathological examination showed necrosis in the gliomas. CONCLUSION: Chemotherapy with angiotensin II-induced hypertension has a better inhibitory effect on rat intracerebral gliomas than chemotherapy alone.

AIM: To observe the role of free radicals in the inhibitory effect of chemotherapy on glioma cells. METHODS: C6 glioma cells were cultured in vitro , and treated with carmustine (B), teniposide (V), or/and nimodipine (N). Furthermore, the glioma-bearing rats were treated with B plus N, B+V+lisplatin (D)+N, or B+V+D+N+angiotensin Ⅱ. The MDA content and superoxide dismutase (SOD) activity in the culture supernatant and cortical brain tissue were assayed. RESULTS: B, V and N significantly decreased MDA content and SOD activity in the supernatant of glioma cell culture and C6 glioma cells. Chemotherapy reduced MDA content and increased SOD activity in the cortical brain tissue of tumor-bearing rats, with highest efficiency in B+V+D+N+angiotensin Ⅱ group. The survival time of tumor-bearing rats in B+V+D+N+angiotensin Ⅱ group was longer than that in other chemotherapy group. CONCLUSION: The antitumor effects of combined chemotherapy may be involved in the free radical metabolism. [

AIM: To investigate the activity of interleukin-1? converting enzyme in transplanted intracerebral rat gliomas under angiotensin II-induced hypertension chemotherapy. METHODS: The brain tumor model was produced in Wistar rats by stereotaxic inoculation of C6 glioma cells (1?10 12 /L). Tumor-bearing rats were treated with carmustine, teniposide and lisplatin (chemotherapy) during angiotensin II-induced hypertension. Then, the survival time of tumor-bearing rats, tumor blood flow, the concentration of drug, volume of gliomas and the activity of interleukin-1? converting enzyme in glioma were examined.RESULTS: The survival time of tumor-bearing rats was significantly longer in chemotherapy with angiotensin II-induced hypertension group than that of chemotherapy alone. In addition, regional tumor blood flow, the concentration of chemotherapeutic drug and the activity of interleukin-1? converting enzyme in transplanted rat gliomas were increased, while the volume of gliomas was decreased in hypertention chemotherapy group compared with chemotherapy alone. CONCLUSION: Chemotherapy with angiotensin II-induced hypertension has a enhancing effect on chemotherapy for improving the drug delivery to tumor tissue by a increased tumor blood flow and enhancing activity of interleukin-1? converting enzyme.

AIM: To investigate the ameliorative effect of water extract of propolis (WEP) preconditioning on mesenteric microcirculation of rats subjected to small intestinal ischemia reperfusion (I/R). METHODS: Thirty-two male Wistar rats were randomly divided into sham, I/R and WEP (100, 200 mg/kg) preconditioning groups. Model of small intestinal I/R injury was made by clamping super mesenteric artery for 45 min followed by 120 min of reperfusion in rats. Mesenteric microcirculation was detected at the end of reperfusion. The degree of small intestinal injury was The content of soluble intercellular adhesion molecule-1 (sICAM-1) in plasma and myeloperoxidase (MPO) activity in intestinal tissue were detected using enzyme linked-immuno-sorbent assay (ELISA) and spectrophotometer, respectively. RESULTS: (1) WEP preconditioning alleviated significantly the pathologic lesion in small intestine, and wet/dry ratio, compared to those in I/R group (P<0.01). (2) The disturbance of the blood flow in microvessel induced by I/R was improved significantly by WEP. In addition, WEP preconditioning alleviated significantly the decrease in diameters of microvessels and microcirculatory blood velocity (P<0.05 vs I/R group) and inhibited the adherence of leukocytes to venule (P<0.01 vs I/R group) in a dose-dependent manner. SICAM-1 content in plasma and MPO activity in intestinal tissue were decreased in WEP preconditioning group, compared to those in I/R group (P<0.05 or P<0.01). CONCLUSION: WEP preconditioning ameliorates mesenteric microcirculation of rats subjected to small intestinal I/R through suppressing the activation of polymorphonuclear neutrophils mediated by ICAM-1.