TY - JOUR
T1 - Modulation of microvessel wall charge by plasma glycoprotein orosomucoid
AU - Curry, F. E.
AU - Rutledge, John C
AU - Lenz, J. F.
PY - 1989
Y1 - 1989
N2 - Haraldsson and Rippe suggested that the circulating glycoprotein orosomucoid (α1-acid glycoprotein) contributes to the net charge on microvessel walls (Acata 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 (α-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 α-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 α-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.
AB - Haraldsson and Rippe suggested that the circulating glycoprotein orosomucoid (α1-acid glycoprotein) contributes to the net charge on microvessel walls (Acata 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 (α-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 α-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 α-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.
KW - alpha 1-acid glycoprotein
KW - capillary permeability
KW - frog mesenteric microvessels
KW - modulation of microvessel permeability to macromolecules
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M3 - Article
C2 - 2589490
AN - SCOPUS:0024330795
VL - 257
JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
SN - 1931-857X
IS - 5
ER -