AJP - Gastrointestinal and Liver Physiology, Vol 258, Issue 5 714-G718, Copyright © 1990 by American Physiological Society
Comparative analysis of protein content in rat mesenteric tissue, peritoneal fluid, and plasma
B. J. Barber, T. J. Schultz and D. L. Randlett
Department of Physiology, Medical College of Wisconsin, Milwaukee 53226.
Albumin, transferrin, and total protein concentrations were measured in the
mesenteric tissue, peritoneal fluid, and plasma of 12
ketamine-Nembutal-anesthetized Sprague-Dawley rats. Tissue samples were
obtained with an 8-mm trephine; tissue water content was determined by a
microgravimetric method to be 5.2 +/- 0.3 microgram water/microgram dry wt.
Peritoneal fluid was collected by capillary action in hematocrit tubes, and
blood samples were taken from a femoral artery catheter. Total protein
concentrations of plasma (5.8 +/- 0.3 g/dl) and peritoneal fluid (2.6 +/-
0.1 g/dl) were determined by Lowry assay. Ratios of peritoneal fluid and
tissue densitogram areas to plasma area were used to calculate total
protein content of peritoneal fluid (2.5 +/- 0.1 g/dl) and tissue (1.8 +/-
0.2 g/dl). Albumin concentrations were 1.1 +/- 0.1 g/dl for tissue, 1.4 +/-
0.1 g/dl for peritoneal fluid, and 2.8 +/- 0.1 g/dl for plasma. Transferrin
concentrations were 0.09 +/- 0.01 g/dl for tissue, 0.13 +/- 0.01 g/dl for
peritoneal fluid, and 0.28 +/- 0.01 g/dl for plasma. Peritoneal fluid
protein concentrations were similar to values found for lymph in previous
studies. Protein concentration in the tissue buttons was significantly less
than that of peritoneal fluid. This contradicts the widely held assumption
that the protein concentration of fluid outside the matrix is
representative of a well-mixed interstitial matrix fluid protein
concentration.
