MODULATION OF MICROVESSEL WALL CHARGE BY PLASMA GLYCOPROTEIN OROSOMUCOID
MODULATION OF MICROVESSEL WALL CHARGE BY PLASMA GLYCOPROTEIN OROSOMUCOID
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DOI：
10.1152/ajpheart.1989.257.5.h1354
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发表时间：
1989-11-01
影响因子：
--
通讯作者：
LENZ, JF
中科院分区：
文献类型：
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作者：
CURRY, FE;RUTLEDGE, JC;LENZ, JF
Haraldsson和Rippe提出，循环糖蛋白orosomucoid（α 1-酸性糖蛋白）有助于微血管壁上的净电荷（Acta Physiol.Scand.129：127-135，1987）。我们测试了他们的假设在单独灌注微血管的青蛙肠系膜通过测量溶质渗透系数的两个球状蛋白质（α-乳白蛋白和核糖核酸酶）具有大致相同的大小（斯托克斯半径，2 nm），但不同的电荷（-11和+3，分别）。在灌注了含乳清类粘蛋白（0.1和1 mg/ml）的林格氏白蛋白灌注液的血管中，α-乳白蛋白的溶质渗透系数降至不含乳清类粘蛋白时的一半[0.47 +/- 0.25（SD）]，核糖核酸酶的溶质渗透系数接近α-乳白蛋白渗透系数的6倍。这两个结果都可以解释，如果orosomucoid增加青蛙肠系膜微血管壁上的净负电荷从11.2到28 meq/l。微血管电荷的类似变化足以解释Haraldsson和Rippe报告的大鼠肌肉微血管中存在类粘蛋白时白蛋白清除率的降低。
Haraldsson and Rippe suggested that the circulating glycoprotein orosomucoid (alpha 1-acid glycoprotein) contributes to the net charge on microvessel walls (Acta Physiol. Scand. 129: 127-135, 1987). We tested their hypothesis in individually perfused microvessels of frog mesentery by measuring solute permeability coefficients of two globular proteins (alpha-lactalbumin and ribonuclease) having approximately the same size (Stokes radius, 2 nm) but different charge (-11 and +3, respectively). In vessels perfused with orosomucoid (0.1 and 1 mg/ml) in a Ringer-albumin perfusate, the solute permeability coefficient of alpha-lactalbumin decreased to one-half [0.47 +/- 0.25 (SD)] the value in the absence of orosomucoid, and the solute permeability coefficient of ribonuclease was close to six times as large as alpha-lactalbumin permeability. Both results may be accounted for if orosomucoid increases the net negative charge on microvessel walls in frog mesentery from 11.2 to 28 meq/l. A similar change in microvessel charge would be more than sufficient to account for the decrease in albumin clearance in the presence of orosomucoid reported by Haraldsson and Rippe in rat muscle microvessels.