Deen W M, Bridges C R, Brenner B M, Myers B D
Am J Physiol. 1985 Sep;249(3 Pt 2):F374-89. doi: 10.1152/ajprenal.1985.249.3.F374.
A heteroporous model of the glomerular filtration barrier was developed and used to interpret dextransieving data in healthy volunteers (normal controls), in patients with nephrotic range proteinuria (grouped as grades I-III, according to severity), and in a group of previously nephrotic patients whose proteinuria was in remission ("resolved controls"). Several hypothetical pore-size distributions were compared in terms of their ability to describe the selective increases in the fractional clearance of large dextrans observed with increasing severity of proteinuria. The most successful model examined was based on the assumption that the major portion of the capillary wall functions as an isoporous membrane, but that a small fraction of the filtrate passes through pores that are unable to discriminate among dextrans of different sizes. The value of the membrane parameter that reflects the relative importance of the nonselective pores was found to increase in parallel with the fractional clearance of immunoglobulin G; it increased progressively in going from normal controls to resolved controls to grades I-III nephrotics. The observed patterns of protein excretion could not, however, be explained entirely by a loss of glomerular size selectivity. Variations in membrane selectivity on the basis of molecular charge and/or molecular configuration are also likely to have been important.
建立了肾小球滤过屏障的异质孔模型，并用于解释健康志愿者（正常对照组）、肾病范围蛋白尿患者（根据严重程度分为I - III级）以及一组蛋白尿已缓解的既往肾病患者（“缓解对照组”）的右旋糖酐通透数据。比较了几种假设的孔径分布在描述随着蛋白尿严重程度增加而观察到的大分子量右旋糖酐分数清除率选择性增加方面的能力。所研究的最成功模型基于这样的假设：毛细血管壁的主要部分起等孔膜的作用，但一小部分滤液通过无法区分不同大小右旋糖酐的孔。发现反映非选择性孔相对重要性的膜参数值与免疫球蛋白G的分数清除率平行增加；从正常对照组到缓解对照组再到I - III级肾病患者，该值逐渐增加。然而，观察到的蛋白质排泄模式不能完全用肾小球大小选择性的丧失来解释。基于分子电荷和/或分子构型的膜选择性变化也可能很重要。
