PERMSELECTIVITY OF GLOMERULAR CAPILLARY WALL - STUDIES OF EXPERIMENTAL GLOMERULONEPHRITIS IN RAT USING NEUTRAL DEXTRAN
PERMSELECTIVITY OF GLOMERULAR CAPILLARY WALL - STUDIES OF EXPERIMENTAL GLOMERULONEPHRITIS IN RAT USING NEUTRAL DEXTRAN
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DOI：
10.1172/jci108395
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发表时间：
1976-01-01
影响因子：
15.9
通讯作者：
BRENNER, BM
中科院分区：
文献类型：
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作者：
CHANG, RLS;DEEN, WM;BRENNER, BM
在肾毒性血清性肾炎(NSN)的早期，向8只慕尼黑-Wistar大鼠注入多分散的[~H]葡聚糖，从而可以直接测量肾小球表面的压力和流量，并允许右旋糖苷[(U/P)右旋糖苷/(U/P)菊粉]在半径范围内的分数清除。尽管肾小球受损，但由于平均净超滤压的代偿性增加，肾小球毛细血管超滤系数显著降低，肾小球滤过率仍保持正常。在NSN大鼠，与正常对照组一样，菊糖不受限制地渗入肾小球毛细血管壁，既不分泌也不重吸收右旋糖苷。对于18、22、26、30、34、38和42 ANG，NSN和对照组大鼠的(U/P)葡聚糖/(U/P)菊粉比值分别为0.90比0.99、0.81比0.97、0.63比0.83、0.38比0.55、0.20比0.30、0.08比0.11和0.02比0.03。使用基于大分子通过毛孔传输的理论，结果表明，在NSN大鼠中，有效毛孔半径与对照组相同，.apprx。50.ANG..在NSN中，总的孔表面积与孔长度的比率，一个衡量孔数量的指标，被减少到.apprx。1/3，可能是由于毛细血管表面积减少所致。肾小球疾病中的蛋白尿可能不是像以前认为的那样简单地由于有效毛孔半径或毛孔数量的增加所致。使用第二种理论方法，基于Kedem-Katchalsky流量方程，NSN组肾小球毛细血管对葡聚糖的通透性略低于对照组，反射系数略高于对照组。
Polydisperse [3H]dextran was infused into 8 Munich-Wistar rats in the early autologous phase of nephrotoxic serum nephritis (NSN), thereby permitting direct measurements of pressures and flows in surface glomeruli and fractional clearances for dextrans [(U/P)dextran/(U/P)inulin] ranging in radius from 18-42 .ANG.. Despite glomerular injury, evidenced morphologically and by a marked reduction in the glomerular capillary ultrafiltration coefficient, the glomerular filtration rate remained normal because of a compensating increase in the mean net ultrafiltration pressure. In NSN rats, as in normal controls, inulin permeated the glomerular capillary wall without measurable restriction, and dextrans were neither secreted nor reabsorbed. For dextran radii of 18, 22, 26, 30, 34, 38, and 42 .ANG., (U/P)dextran/(U/P)inulin in NSN and control rats, respectively, averaged 0.90 vs. 0.99, 0.81 vs. 0.97, 0.63 vs. 0.83, 0.38 vs. 0.55, 0.20 vs. 0.30, 0.08 vs. 0.11, and 0.02 vs. 0.03. Using a theory based on macromolecular transport through pores, the results indicate that in NSN rats, effective pore radius is the same as in controls, .apprx. 50 .ANG.. In NSN the ratio of total pore surface area to pore length, a measure of the number of pores, is reduced to .apprx. 1/3 that of control, probably due to a reduction in capillary surface area. Proteinuria in glomerular disease is probably not due simply to increases in effective pore radius or number of pores, as previously believed. Using a 2nd theoretical approach, based on the Kedem-Katchalsky flux equations, dextran permeability across glomerular capillaries was slightly lower, and reflection coefficient slightly higher in NSN than in control rats.