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MINIREVIEW
Acute Pancreatitis:
Proteinase-Activated Receptor-2 as
Dr. Jekyll and Mr. Hyde
R. MATĚJ1,2, D. HOUSA2, T.
OLEJÁR3
1Department of Pathology, Teaching Thomayer Hospital,
Prague, 2 Department of Pathology, Teaching Hospital
Královské Vinohrady, Charles University, Prague, 3
Institute of Biophysics, First Faculty of Medicine, Charles
University, Prague, Czech Republic
Received April 25, 2005
Accepted September 30, 2005
On-line available December 12, 2005
Summary
„Proteinase-activated“ receptor-2 (PAR-2) is a G protein-coupled
transmembrane receptor with seven transmembrane domains
activated by trypsin. It has been shown in the pancreatic tissue
that PAR-2 is involved in duct/acinary cells secretion, arterial
tonus regulation and capillary liquid content turnover under
physiological conditions. These above mentioned structures play
an important role during the development of acute pancreatitis
and are profoundly influenced by a high concentration of trypsin
enzyme after its secretion into the interstitial tissue from the
basolateral aspect of acinar cells. Among the other factors, it
is the increase of interstitial trypsin concentration followed
rapidly by PAR-2 action on pancreatic vascular smooth muscle
cells that initiates ischemic changes in pancreatic parenchyma
and that finally leads to necrosis of the pancreas. Consequent
reperfusion perpetuates changes leading to the acute
pancreatitis development. On the contrary, PAR-2 action on both
exocrine and duct structures seems to play locally a protective
role during acute pancreatitis development. Moreover, PAR-2
action is not confined to the pancreas but it contributes to the
systemic vascular endothelium and immune cell activation that
triggers the systemic inflammatory response syndrome (SIRS)
contributing to an early high mortality rate in severe disease.
Key words
PAR-2 • Acute pancreatitis • Trypsin
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