Brunner H
Acta Med Austriaca Suppl. 1975;3:1-39.
Intestinal perfusion methods with a nonabsorbable marker allow an exact quantitative determination of intestinal absorption and secretion provided that methodological pitfalls are avoided. A modified technique is applied to the simultaneous measurement of biliary and pancreatic secretion during and depending on emptying of a mixed test meal. A duodenal segment was perfused with an isotonic polyethyleneglycol solution (PEG). Reinjection of duodenal aspirates maintained a normal enterohepatic circulation of bile acids (interruption less than 10%). The perfusion was performed in healthy volonteers over a period of 12 to 24 hours, with three mixed formula meals containing 51CrCl3 as a marker ingested at conventional feeding hours. Influence of meal size was studied by means of a high caloric (40 Kcal/b. wt. per day) test meal. Patients with cholesterol gallstones and cirrhosis of the liver only received one formula test meal of 300 Kcal. Instead of concentrations output of trypsin, lipase, bile acids and cholesterol (the latter corrected for duodenal absorption) was calculated from the dilution of PEG in the duodenal juice and gastric emptying was determined by following quantitatively the flow of 51CrCl3. Gastric emptying can be expressed by a single exponential function over most of the time. Only the last 60-100 Kcals were expelled by the stomach at a faster rate. The daily biliary and pancreatic secretion depend indirectly on the amount of food ingested. But during the day light hours (with continuous meal flow), secretion was similar in high and low caloric subjects, while a significant difference became obvious during night hours corresponding to differences in gastric emptying time. Mean hourly output of bile acid, biliary cholesterol, trypsin and lipase is independent from meal size and secretion of pancreatic enzymes reaches the values close to those after maximal stimulation by i.v. CCK-PZ. Output of pancreatic enzymes does not differ in health and gallstone disease or cirrhosis of the liver respectively. Since during digestion in normals approximately one forth of the bile acid pool is secreted hourly into the gut, the number of daily enterohepatic cycles of bile acids can be calculated by 4-6. Patients with cholesterol gallstones maintain normal bile acid output by enhanced cycling of the small pool: An average of 50% of the pool passed the duodenum per hour. A decreased bile acid pool is also present in cases of advanced cirrhosis of the liver. However, hourly output of bile acids in these patients is significantly less than in mild cirrhosis (with normal bile acid pool) or normal controls. Therefore the hourly fraction of the pool secreted is similar to healthy subjects. These findings provide an important information to explain abnormalities in bile acid metabolism in cirrhosis.
使用不可吸收标记物的肠道灌注方法能够精确地定量测定肠道吸收和分泌情况，前提是要避免方法上的缺陷。一种改良技术被用于在混合试验餐排空期间及根据其排空情况同时测量胆汁和胰腺分泌。用等渗聚乙二醇溶液（PEG）灌注十二指肠段。回注十二指肠抽吸物可维持胆汁酸正常的肠肝循环（中断时间少于10%）。在健康志愿者中进行灌注，持续12至24小时，在常规进餐时间摄入三份含51CrCl3作为标记物的混合配方餐。通过高热量（40千卡/体重/天）试验餐研究餐量的影响。患有胆固醇结石和肝硬化的患者仅接受一份300千卡的配方试验餐。通过PEG在十二指肠液中的稀释来计算胰蛋白酶、脂肪酶、胆汁酸和胆固醇的输出量（后者已校正十二指肠吸收情况），并通过定量跟踪51CrCl3的流量来测定胃排空情况。胃排空在大多数时间可用单一指数函数表示。只有最后60 - 100千卡由胃以更快的速度排出。每日胆汁和胰腺分泌间接取决于摄入食物的量。但在白天（餐流持续），高热量和低热量受试者的分泌情况相似，而在夜间，对应于胃排空时间的差异，差异变得明显。胆汁酸、胆汁胆固醇、胰蛋白酶和脂肪酶的平均每小时输出量与餐量无关，胰腺酶的分泌量达到接近静脉注射胆囊收缩素 - 促胰酶素最大刺激后的数值。胰腺酶的输出量在健康人群、胆结石疾病患者或肝硬化患者中并无差异。由于在正常消化过程中，大约四分之一的胆汁酸池每小时分泌到肠道中，胆汁酸的每日肠肝循环次数可计算为4 - 6次。患有胆固醇结石的患者通过增强小胆汁酸池的循环来维持正常的胆汁酸输出：平均每小时有50%的胆汁酸池通过十二指肠。在晚期肝硬化病例中也存在胆汁酸池减少的情况。然而，这些患者胆汁酸的每小时输出量明显低于轻度肝硬化（胆汁酸池正常）患者或正常对照组。因此，分泌的胆汁酸池每小时的比例与健康受试者相似。这些发现为解释肝硬化中胆汁酸代谢异常提供了重要信息。
