Ethanol/lipid metabolism, dysfunction of ion transport, and pathogenesis of alcoholic pancreatitis

1.检测日本慢性胰腺炎患者囊性纤维化跨膜传导调节因子(CFTR)基因的突变和多态性(TG重复、PolyT、M470V、Q1352H、R1453W)。没有检测到任何导致囊性纤维化的突变。酒精性胰腺炎患者TG基因频率较高(12/12)。结论：1.在特发性胰腺炎患者中，V470/V470基因型频率较高。为了评价CFTRCl-通道功能，我们建立了“手指汗氯化物试验”，用拇指握住装有100μL水的小试管采集无感汗液中的氯离子浓度，并用汗水计测量出汗率。样品中的氯离子含量可用毛细管电泳法或更容易用高灵敏的电极来测定。用Δ-F小鼠建立囊性胰管纤维化模型，观察胰管顶膜Na~+-H~+交换活性。ΔF/ΔF导管顶端NHE活性显著升高，可能导致胰液pH值下降。本实验观察了甲醇、乙醇、丙醇、正丁醇等一系列短链醇类化合物对豚鼠胰管小叶间段cAMP刺激的液体分泌和细胞内钙离子浓度的影响。甲醇和乙醇促进液体分泌，引起细胞内钙离子一过性升高。反之，丙醇和丁醇可抑制细胞液体分泌，降低细胞内钙离子浓度。这种“切断效应”表明酒精直接作用于胰管细胞的某些离子通道。

1. Mutations and polymorphisms (TG repeats, poly T, M470V, Q1352H, R1453W) of CFTR (cystic fibrosis transmembrane conductance regulator) were examined in Japanese patients with chronic pancreatitis. None of the cystic fibrosis-causing mutations were detected. Frequency of the genotype TG(12/12) was higher in alcoholic pancreatitis. Frequency of the genotype V470/V470 was higher in idiopathic pancreatitis.2. To estimate CFTR Cl^- channel function, we established "finger sweat chloride test" to measure Cl^- concentration in insensible sweat, which sweat is collected by holding a small tube containing 100 μl water with the thumb and the sweat rate is measured by a perspiration meter. The Cl^- content in the sample is measured by capillary electrophoresis or more easily by a highly sensitive electrode.3. The activity of Na^+-H^+ exchange (NHE) in the apical membrane was examined in luminally-microperfused interlobular pancreatic duct segments isolated from ΔF mice, a cystic fibrosis model. The apical NHE activity significantly increased in ΔF/ΔF ducts, which may cause pH decrease of pancreatic juice.4. Effects of a series of short-chain alcohols (methanol, ethanol, propanol, and butanol) on cAMP-stimulated fluid secretion and intracellular Ca^<2+> concentration were examined in interlobular pancreatic duct segments isolated from guinea-pig. Methanol and ethanol enhanced fluid secretion and caused a transient increase of intracellular Ca^<2+>. On the contrary, propanol and butanol inhibited fluid secretion and lowered intracellular Ca^<2+>. This "cut-off effect" suggests alcohols act directly on some ion channels of pancreatic duct cells.