Permeability of rabbit skin and muscle microvasculature after saline infusion

The protein permeability characteristics of skin and skeletal muscle microvasculature were examined in rabbits following saline infusion equivalent to 9.5% of the body weight. Prenodal lymph was collected from these two tissues. In muscle the lymph flow increased from 0.94 ± 0.12 to 2:91 ± 0.36 microliters (μl)/min over baseline, and the lymph-to-plasma total protein ratio (R_T) decreased from 0.561 ± 0.033 to 0.364 ± 0.016. In skin the lymph flow increased from 1.56 ± 0.25 to 4.01 ± 0.64 microliters (μl)/min, and the R_T decreased from 0.340 ± 0.014 to 0.230 ± 0.016. In both tissues, the lymph-to-plasma ratios for albumin were greater than those for immunoglobulin G in controls and showed the same relationship after infusion. Thus, membrane selectivity and protein sieving did not change with saline expansion of the plasma volume. No change in microvasculature permeability occurred in these tissues, which contain 70% of the interstitial volume, following a large intravenous infusion of crystalloid.