Effects of particulates and lipids on the hydraulic conductivity of Matrigel
Effects of particulates and lipids on the hydraulic conductivity of Matrigel
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DOI：
10.1152/japplphysiol.01245.2007
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发表时间：
2008-08-01
影响因子：
3.3
通讯作者：
Johnson, Mark
中科院分区：
文献类型：
--
作者：
McCarty, William J.;Chimento, Melissa F.;Johnson, Mark
结缔组织的水力导电性是由细胞外基质的精细超微结构和间隙空间中较大颗粒的作用决定的。在这项研究中，我们通过研究30或90纳米直径的乳胶纳米球或低密度脂蛋白（LDL）对基底膜基质Matrigel的水力导电性的影响来探索这种关系。测定了以4.8%质量分数添加乳胶纳米球或LDL颗粒的Matrigel的导电性，并与单独添加的Matrigel的导电性进行了比较。通过透射电子显微镜观察凝胶中ldl衍生的脂质，可以看到聚集成500纳米大小的颗粒。将这些材料添加到介质中显著降低了其水力导电性，其中ldl衍生的脂质比乳胶纳米球具有更大的影响。采用Debye-Brinkman理论预测了颗粒的加入对介质导电性的影响。理论预测与在介质中加入乳胶纳米球的结果吻合得很好。然而，低密度脂蛋白降低的水力传导率比理论预测的要大得多。嵌入细胞外基质的刚性颗粒理论模型的验证表明，它可用于预测颗粒（如胶原蛋白、弹性蛋白、细胞）对结缔组织中细丝状基质（蛋白聚糖）的水力导电性的影响。此外，类脂颗粒对水力传导的影响大于预期，可能会放大与脂质积累相关的病理，例如黄斑变性期间视网膜Bruch膜和动脉粥样硬化时血管壁的脂质积累。
The hydraulic conductivity of a connective tissue is determined both by the fine ultrastructure of the extracellular matrix and the effects of larger particles in the interstitial space. In this study, we explored this relationship by examining the effects of 30- or 90-nm-diameter latex nanospheres or low-density lipoproteins (LDL) on the hydraulic conductivity of Matrigel, a basement membrane matrix. The hydraulic conductivity of Matrigel with latex nanospheres or LDL particles added at 4.8% weight fraction was measured and compared with the hydraulic conductivity of Matrigel alone. The LDL-derived lipids in the gel were visualized by transmission electron microscopy and were seen to have aggregated into particles up to 500 nm in size. The addition of these materials to the medium markedly decreased its hydraulic conductivity, with the LDL-derived lipids having a much larger effect than did the latex nanospheres. Debye-Brinkman theory was used to predict the effect of addition of particles to the hydraulic conductivity of the medium. The theoretical predictions matched well with the results from adding latex nanospheres to the medium. However, LDL decreased hydraulic conductivity much more than was predicted by the theory. The validation of the theoretical model for rigid particles embedded in extracellular matrix suggests that it could be used to make predictions about the influence of particulates (e. g., collagen, elastin, cells) on the hydraulic conductivity of the fine filamentous matrix (the proteoglycans) in connective tissues. In addition, the larger-than-predicted effects of lipidlike particles on hydraulic conductivity may magnify the pathology associated with lipid accumulation, such as in Bruch's membrane of the retina during macular degeneration and the blood vessel wall in atherosclerosis.