Assessment of protein permeability in normal human systemic circulation

Carl Shanholtz, Peter White, Solbert Permutt, Jimmie T. Sylvester, Roy Brower

Research output: Contribution to journalArticle

Abstract

Vascular permeability to oncotic agents is an important determinant of transvascular fluid flux (J) and systemic fluid balance. In this study, a technique was developed to measure protein reflection coefficients (σ) for albumin (Alb), immunoglobulin (Ig) G, and IgM in the intact human systemic circulation to evaluate the role of vascular protein permeability in health and disease. A mathematical model was developed to calculate σ in the forearm circulation from changes in venous hematocrit and protein concentration that occur during edema formation. Assumptions required for the model were validated in an initial set of experiments in normal subjects when edema was induced by inflating a pneumatic cuff on the upper arm. A second series of experiments assessed σ for Alb, IgG, and IgM in men (n = 7) and in women in the follicular (n = 5) and luteal (n = 4) phases of the menstrual cycle. There was an increasing trend in σ with molecular size in aggregated subjects [σ(Alb) = 0.81 ± 0.12 (SE), σ(IgG) = 0.88 ± 0.12, σ(IGM) = 0.92 ± 0.18; P = 0.088]. These values were consistent with those obtained with in vitro preparations. σ values were lower in women in the luteal than in the follicular phase (P = 0.047). We conclude that the assumptions required for this model can be achieved in the intact forearm circulation and that there are menstrual phase-related differences in vascular protein permeability in normal women.

Original languageEnglish (US)
Pages (from-to)H1049-H1057
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume273
Issue number3 42-3
StatePublished - 1997

Keywords

  • Capillary leak
  • Edema
  • Reflection coefficient
  • Vascular permeability

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Assessment of protein permeability in normal human systemic circulation'. Together they form a unique fingerprint.

Cite this