al. have shown that IL-33 augments substance P-induced human mast cell secretion of vascular endothelial growth factor (VEGF), indicating a synergism between IL-33 and substance P on mast cell activation.[12] Increased pancreatic levels of substance P, circulating levels of histamine, and mast cell degranulation in the pancreas and lung in ligation-induced acute pancreatitis in mice and rats is supportive evidence implicating a role for mast cells in disease pathogenesis in this experimental model. This evidence concerns the gene IL33 and acute pancreatitis.