Intestinal capillary endothelial barrier changes in severe acute pancreatitis

To study changes of the small intestine capillary endothelial barrier during severe acute pancreatitis (SAP) in a rat model.

A SAP rat model was created, serum and ascites albumin and amylase were measured, and the Evans blue assay was used to measure intestinal capillary leakage. Capillary endothelial barrier changes were examined via electron microscopy. Intestinal VASP and MMP-9 expression was determined by real-time quantitative PCR and Western blotting.

An increase of small intestinal capillary leakage was observed in SAP rats. Widened gaps between small intestinal capillary endothelial cells and swelling and fracture of the basement membrane were found. VASP expression at 12 hours was significantly greater than at >6 hours; however, expression at 24 hours was significantly less than at 12 hours (both, p<0.05). Increased MMP-9 mRNA and protein expression in intestinal tissues was observed. MMP-9 expression at 12 hours was significantly greater than at 6 hours; however, expression at 24 hours was significantly less than at 12 hours (both p<0.05).

MMP-9, which may be upregulated during SAP, may lead to degradation of the capillary endothelial basement membrane. Increased VASP may result in rearrangement of the endothelial cytoskeleton, which can change capillary endothelial cell connections.