单光子发射计算机断层显像对自制注射用神经生长因子-脂质体脑靶向性研究

目的：通过单光子发射计算机断层显像(single photon emission computerized tomography，SPECT)技术对比分析不同剂型的神经生长因子(nerve growth factor，NGF)经静脉注射后在体内的靶向分布情况。方法：将^99mTc]-NGF川脂质体包裹后，按照以下条件处理：将包裹含有4．0mCi^99mTc]-NGF的脂质体．注射至新西兰兔体内，利用SPECT分析其在脑部分布的百分数。对照组以相同放射剂量的^99mTc]—NGF、^99mTc]—NGF—普通脂质体。处理。结果：自制注射用脂质体、组包裹的^99mTc]—NGF经SPECT显像，其在脑部的放射性计数较高，而^99mTc]—NGF组几乎全部从泌尿系统代谢、^99mTc]—NGF—普通脂质体。组基本被网状内皮系统吞噬后沉积于肝脏。结论：此自制NGF—脂质体A具有一定的脑组织靶向性，为携带药物透过血脑屏障(blood—brain—barrier，BBB)奠定基础。

Research of NGF-Liposome Ability of Target to Brain by Imaging with Single Photon Emission Computerized Tomography

Objective: To compare the brain target distribution of NGF in different forms after it was injected into rabbits body by imaging with SPECT. Methods: The 4.0 mCi of-NGF packed with liposomeA, 4.0 mCi of 99mTc-NGF packed with liposomeB and free-NGF were differently injected into the rabbit by the vein of ear border. SPECT was used to detect the distribution of -NGF. And then the ratio of radioactivity counts between brain and all was calculated to describe the character of distribution in brain. Results: The results of imaging with SPECT showed that -NGF packed with liposomeA was aggregated in brain; -NGF was evacuated through urinary system. In addition, 99mTc-NGF packed with liposomeB was aggregated in liver. Conclusion: The NGF packed with liposomeA possessed ability of target to brain. It could take NGF across the blood-brain-barrier(BBB).