Early microcirculatory derangement in mild and severe pancreatitis models in mice

An in vivo microscopic technique was used to clarify the increase in microv ascular permeability and enhanced leukocyte-endothelium interaction of panc reatic microcirculation in experimental pancreatitis of differing severity. Using bovine albumin fluorescein isothiocyanate (FITC) and carboxyfluoresc ein diacetate succiuimidyl ester (CFDASE) as tracers, the change in permeab ility and the behavior of leukocytes in the acinar microcirculation were qu antified during the initial 1, 2, 6, and 12h after the induction of caerule in pancreatitis in mice. Cold stress was added to produce the severe model. It was revealed that the early microcirculatory changes in the pancreas of caerulein pancreatitis included the increased permeability of endothelial lining and an accumulation of extravasated fluid in the perilobular space, which were more severe if cold stress was added. A decrease in flow velocit y was also noted 2h after the onset of severe pancreatitis. Leukocyte adher ence to the endothelial cells was not observed during the first 12h in eith er model of severity. In contrast, observation of the hepatic microcirculat ion revealed a significant number of adherent leukocytes 2h after the induc tion of severe pancreatitis. These results suggest that during the early co urse of acute pancreatitis, leukocyte adherence in the pancreatic microcirc ulation is a secondary event following the increase in pancreatic vascular permeability.