Albumin and IgG in skin and skeletal muscle after plasmapheresis with saline loading

Abstract

The acute effect of removing plasma equivalent to 1.7% body wt and replacing it with saline equivalent to 10% body wt on the extravascular distribution of water, albumin, and immunoglobulin G (IgG) in skin and skeletal muscle was studied in anesthetized rabbits. The plasma protein concentration decreased by 43%. Prenodal lymph was collected from hindpaw skin or skeletal muscle. The extracellular and plasma volumes in excised tissue samples were measured using 51Cr-labeled ethylenediaminetetraacetic acid and 125I-labeled albumin, respectively. The protein spaces were calculated from measurements of endogenous albumin and IgG concentrations using immunochemical techniques. Lymph flow from both tissues increased more than twice control, whereas the lymph total protein concentration decreased to less than one-half control. Three to six hours after the saline infusion, the skin interstitial volume was 30% greater than control, whereas the extravascular masses of albumin and IgG were 20% greater than control. For muscle, the interstitial volume was twice the control value, whereas the extravascular masses of albumin and IgG were not significantly altered. There was a large decrease in the lymph protein concentration after acute plasmapheresis. However, there was not an acute decrease in the extravascular albumin or IgG masses from skin or skeletal muscle. This may be due to the presence of the collagen matrix and edema fluid.