Masanobu Nakashima

Effects of granulocyte colony-stimulating factor on neutrophils and inflammatory cytokines in the early stage of severe acute pancreatitis in rats

BackgroundThe high mortality rate of severe acute pancreatitis (SAP) is closely associated with secondary infections of pancreatic and peripancreatic tissues. It was reported that granulocyte colony-stimulating factor (G-CSF) increased the number of leukocytes and enhanced their functions. However, an inflammatory response may be enhanced by an increased number of leukocytes. Our purpose was to study the roles of G-CSF in peritoneal-exudate neutrophils and inflammatory cytokines in the early stage of experimental SAP.MethodsSAP was induced by injecting 0.2 ml of 3% taurocholate acid into the biliopancreatic duct in male Wistar rats. G-CSF (90 µg/kg body weight) or saline was administered 1 h before the SAP induction. The number of neutrophils and their phagocytic and bactericidal activities were evaluated, and the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in plasma and ascitic fluid were measured 1 h and 3 h after the SAP induction.ResultsThe number of peritoneal-exudate neutrophils (PENs) at 3 h was increased by G-CSF administration (81 ± 50 × 105 cells/total exudate), as compared with that shown with saline administration (28 ± 13 × 105 cells/total exudate; P < 0.05). The numbers of phagocytic and bactericidal neutrophils were also elevated by G-CSF administration. G-CSF administration did not increase the concentrations of TNF-α, IL-6, and IL-1β in the plasma and ascitic fluid.ConclusionsG-CSF increases the numbers of neutrophils and enhances their functions against bacteria, but it does not enhance intraabdominal and systemic inflammatory responses in the early stage of SAP.

Medium-term effects of endoscopic papillary balloon dilation on gallbladder motility

BACKGROUND Endoscopic papillary balloon dilation (EPBD) for removal of bile duct stones tends to preserve papillary function. However, EPBD may exert beneficial or deleterious effects on gallbladder motility. This was a prospective, medium-term investigation (2 years) of the effects of EPBD on gallbladder motility. METHODS Twelve patients with intact gallbladders (6 with and 6 without gallbladder stones) who underwent EPBD for choledocholithiasis were enrolled in this study. Gallbladder motility was examined before EPBD and at 7 days, 1 month, 1 year, and 2 years after EPBD. Gallbladder volumes, measured after fasting and after ingestion of dried egg yolk, were determined by US. RESULTS All patients were asymptomatic during the 2-year follow-up period. Before EPBD, particularly in patients with cholelithiasis, the gallbladder had a larger fasting volume and lower yolk-stimulated maximum contraction compared with normal control subjects. Seven days after EPBD, fasting volume was decreased and maximum contraction was increased, both significantly compared with pre-EPBD values and regardless of the presence or absence of gallbladder stones. At 1 month, 1 year, and 2 years after EPBD, these changes were far less evident and gallbladder function did not differ significantly from baseline. CONCLUSION EPBD does not adversely affect gallbladder motility in the medium-term (2 years). In terms of gallbladder motility, EPBD does not appear to increase the future risk of acute cholecystitis or gallbladder stone formation.