Protease activity increases in plasma, peritoneal fluid, and vital organs after hemorrhagic shock in rats

• Published in: PloS one 2012-03, Vol.7 (3), p.e32672-e32672
• Main Authors: Altshuler, Angelina E, Penn, Alexander H, Yang, Jessica A, Kim, Ga-Ram, Schmid-Schönbein, Geert W
• Format: Article
• Language: English
• Subjects: Animals; Ascitic Fluid - enzymology; Benzamidines; Biology; Blood pressure; Body Fluids - enzymology; Brain; Brain - drug effects; Brain - enzymology; Casein; Chymotrypsin; Compartments; Digestive enzymes; Elastase; Enzymes; Gelatin; Gelatinase; Gelatinase B; Guanidines - pharmacology; Health aspects; Heart; Hemorrhage; Hemorrhagic shock; Hydrolases; Immunoblotting; Intestine; Ischemia; Liver; Liver - drug effects; Liver - enzymology; Lung - drug effects; Lung - enzymology; Lungs; Male; Matrix Metalloproteinase 9 - metabolism; Matrix Metalloproteinase Inhibitors; Matrix metalloproteinases; Medicine; Myocardium - enzymology; Organs; Pancreas; Peritoneal Cavity; Peritoneal fluid; Peritoneum; Peroxidase - antagonists & inhibitors; Peroxidase - metabolism; Plasma proteins; Protease; Protease inhibitors; Proteases; Proteins; Rats; Rats, Wistar; Receptors; Reperfusion; Rodents; Serine; Serine Proteases - blood; Serine Proteases - metabolism; Serine proteinase; Serine Proteinase Inhibitors - pharmacology; Shock; Shock, Hemorrhagic - enzymology; Shock, Hemorrhagic - physiopathology; Shock, Hemorrhagic - prevention & control; Small intestine; Substrate Specificity; Substrates; Thrombin; Trypsin; Trypsin - metabolism; Tumor necrosis factor-TNF
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0032672

Hemorrhagic shock (HS) is associated with high mortality. A severe decrease in blood pressure causes the intestine, a major site of digestive enzymes, to become permeable - possibly releasing those enzymes into the circulation and peritoneal space, where they may in turn activate other enzymes, e.g. matrix metalloproteinases (MMPs). If uncontrolled, these enzymes may result in pathophysiologic cleavage of receptors or plasma proteins. Our first objective was to determine, in compartments outside of the intestine (plasma, peritoneal fluid, brain, heart, liver, and lung) protease activities and select protease concentrations after hemorrhagic shock (2 hours ischemia, 2 hours reperfusion). Our second objective was to determine whether inhibition of proteases in the intestinal lumen with a serine protease inhibitor (ANGD), a process that improves survival after shock in rats, reduces the protease activities distant from the intestine. To determine the protease activity, plasma and peritoneal fluid were incubated with small peptide substrates for trypsin-, chymotrypsin-, and elastase-like activities or with casein, a substrate cleaved by multiple proteases. Gelatinase activities were determined by gelatin gel zymography and a specific MMP-9 substrate. Immunoblotting was used to confirm elevated pancreatic trypsin in plasma, peritoneal fluid, and lung and MMP-9 concentrations in all samples after hemorrhagic shock. Caseinolytic, trypsin-, chymotrypsin-, elastase-like, and MMP-9 activities were all significantly (p