Raimondo M, DiMagno E P
Gastrointestinal Research Unit, Mayo Clinic, Rochester, Minnesota.
Gastroenterology. 1994 Jul;107(1):231-5. doi: 10.1016/0016-5085(94)90081-7.
BACKGROUND/AIMS: Treatment of pancreatic steatorrhea with porcine lipase is unsatisfactory because it is rapidly denatured by acidic intraluminal conditions. The aim of this study was to determine if bacterial lipase is resistant to acid denaturation and is active in the presence of bile acids by comparing its stability with that of porcine lipase in gastric and duodenal juice obtained from six patients undergoing a cholecystokinin octapeptide pancreatic function test.
After inactivating native lipolytic activity, both juices were altered to simulate fasting and postprandial conditions in normal patients and patients with pancreatic insufficiency. Gastric juice was adjusted to pH 2, 3, 4, or 6, duodenal juice to pH 4 or 6, and bile acid concentrations to 4 or 12 mmol/L. Nutrients were added to one half of the samples. Initial bacterial or porcine lipolytic concentrations were 25 or 250 U/mL. After a 1-hour incubation at 37 degrees C, lipolytic activity was remeasured.
In gastric juice, more bacterial lipolytic activity survived than porcine lipolytic activity at both concentrations in the absence of nutrients and at a concentration of 25 U/mL with nutrients (P < 0.05). In duodenal juice, more bacterial lipolytic activity survived than porcine activity at pH 4 under all test conditions (P < 0.05).
Bacterial lipolytic activity should survive better within the gastrointestinal lumen than porcine lipolytic activity and be more effective to treat steatorrhea.
背景/目的：用猪胰脂肪酶治疗胰腺性脂肪泻效果不佳，因为它会迅速被管腔内的酸性环境变性。本研究的目的是通过比较从6名接受八肽胆囊收缩素胰腺功能试验患者获得的胃液和十二指肠液中细菌脂肪酶与猪胰脂肪酶的稳定性，来确定细菌脂肪酶是否耐酸变性以及在胆汁酸存在的情况下是否具有活性。
在使天然脂解活性失活后，将两种消化液进行改变以模拟正常患者和胰腺功能不全患者的空腹和餐后状态。将胃液的pH值调至2、3、4或6，十二指肠液的pH值调至4或6，胆汁酸浓度调至4或12 mmol/L。在一半的样本中添加营养物质。初始细菌或猪胰脂解浓度为25或250 U/mL。在37℃孵育1小时后，重新测量脂解活性。
在胃液中，在无营养物质时以及在添加营养物质且浓度为25 U/mL时，两种浓度下细菌脂解活性的存活量均高于猪胰脂解活性（P < 0.05）。在十二指肠液中，在所有测试条件下，pH值为4时细菌脂解活性的存活量均高于猪胰脂解活性（P < 0.05）。
细菌脂解活性在胃肠道内的存活情况应比猪胰脂解活性更好，并且在治疗脂肪泻方面更有效。
