Nariai T, DeGeorge J J, Greig N H, Rapoport S I
Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, Maryland.
J Neurosurg. 1991 Apr;74(4):643-9. doi: 10.3171/jns.1991.74.4.0643.
Lipid metabolism of an intracerebrally implanted brain tumor and normal brain was investigated in awake Fischer 344 rats using intravenously injected [9,10(-3)H]-palmitate as a probe. A suspension of Walker 256 carcinosarcoma cells (250 cells in 5 microliters medium), with or without 1% low-melting-point agar, was implanted into the caudate nucleus of rats 8 to 9 weeks old. Control animals received an intracerebral injection without tumor cells. Seven days after implantation, awake rats were infused intravenously for 5 minutes with [9,10(-3)H]-palmitate (6.4 mCi/kg). The rats were killed 20 minutes after initiation of the infusion and coronal brain slices were obtained for quantitative autoradiography and light histological study. Tumor cell masses were histologically well demarcated from the surrounding brain tissue. Tumor tissue incorporation of [9,10(-3)H]-palmitate was heterogeneous, ranging on average from 3.1- to 6.1-fold greater than in the corresponding contralateral brain. In addition, incorporation corresponded to regional tumor cell density. The incorporation rate constant of [9,10(-3)H]-palmitate in tumor was significantly increased compared to control brain and was independent of tumor size. Necrotic areas within tumors showed no incorporation of radiolabeled palmitate. Brain surrounding the tumors and control injection sites showed reactive gliosis, and possessed 30% greater incorporation of [9,10(-3)H]-palmitate than contralateral normal brain. These results suggest that [9,10(-3)H]-palmitate can be used to image brain tumors in vivo, measuring turnover and/or synthesis of tumor and brain lipid.
利用静脉注射的[9,10(-3)H]-棕榈酸作为探针，在清醒的Fischer 344大鼠中研究了脑内植入脑肿瘤和正常脑的脂质代谢。将Walker 256癌肉瘤细胞悬液（5微升培养基中含250个细胞），添加或不添加1%低熔点琼脂，植入8至9周龄大鼠的尾状核。对照动物接受无肿瘤细胞的脑内注射。植入后7天，对清醒大鼠静脉输注[9,10(-3)H]-棕榈酸5分钟（6.4毫居里/千克）。输注开始20分钟后处死大鼠，获取冠状脑切片用于定量放射自显影和光镜组织学研究。肿瘤细胞团在组织学上与周围脑组织界限清晰。肿瘤组织对[9,10(-3)H]-棕榈酸的摄取存在异质性，平均比相应对侧脑高3.1至6.1倍。此外，摄取与区域肿瘤细胞密度相对应。与对照脑相比，肿瘤中[9,10(-3)H]-棕榈酸的摄取速率常数显著增加，且与肿瘤大小无关。肿瘤内的坏死区域未显示放射性标记棕榈酸的摄取。肿瘤周围的脑组织和对照注射部位出现反应性胶质增生，[9,10(-3)H]-棕榈酸的摄取比同侧正常脑高30%。这些结果表明，[9,10(-3)H]-棕榈酸可用于体内脑肿瘤成像，测量肿瘤和脑脂质的周转和/或合成。
