Mauk M R, Gamble R C
Proc Natl Acad Sci U S A. 1979 Feb;76(2):765-9. doi: 10.1073/pnas.76.2.765.
The rate of phospholipid vesicle disruption in specific tissues of the mouse was followed by gamma-ray perturbed angular correlation (PAC) spectroscopy. In these studies, high levels of 111In-nitrilotriacetic acid complex are contained in unilamellar vesicles consisting of distearoyl phosphatidylcholine, cholesterol, and small amounts of other lipids which modify the surface properties. The PAC technique monitors the extent of vesicle breakup by measuring a time-integrated perturbation factor, less than G22 (infinity) greater than. As the vesicles are broken open in vivo, the released 111In3+ ions quickly bind to macromolecules and the less than G22 (infinity) greater than value decreases substantially. After administration of vesicles by various routes (intravenous, intraperitoneal, subcutaneous, and oral), the radioactivity and less than G22 (infinity) greater than values were determined for several tissues at intervals up to 24 hr. We conclude from these data that (i) the PAC technique in conjunction with standard gamma counting methods provides unique information on the condition and location of vesicles in specific tissues, (ii) significant differences in vesicle integrity are found in various tissues, and (iii) both the means of administration and the presence of surface charge affect the vesicle stability and distribution. The carbohydrate analogues of cholesterol affect vesicle stability but not distribution.
通过γ射线扰动角关联（PAC）光谱法跟踪小鼠特定组织中磷脂囊泡的破坏率。在这些研究中，由二硬脂酰磷脂酰胆碱、胆固醇和少量改变表面性质的其他脂质组成的单层囊泡中含有高水平的铟-111三氮乙酸络合物。PAC技术通过测量一个时间积分扰动因子来监测囊泡破裂的程度，该因子小于G22（无穷大）大于。随着囊泡在体内破裂，释放的铟-111 3+离子迅速与大分子结合，小于G22（无穷大）大于值大幅下降。通过各种途径（静脉内、腹膜内、皮下和口服）给予囊泡后，在长达24小时的间隔内测定了几个组织的放射性和小于G22（无穷大）大于值。我们从这些数据中得出以下结论：（i）PAC技术与标准γ计数方法相结合可提供关于特定组织中囊泡状态和位置的独特信息；（ii）在不同组织中发现囊泡完整性存在显著差异；（iii）给药方式和表面电荷的存在都会影响囊泡的稳定性和分布。胆固醇的碳水化合物类似物会影响囊泡稳定性，但不会影响其分布。
