Lake-Bakaar G, Beidas S
Academic Department of Medicine, Royal Free Hospital School of Medicine, London, England.
Pancreas. 1991 Nov;6(6):673-8. doi: 10.1097/00006676-199111000-00009.
The route of entry of immunoreactive secretin into the duodenal lumen during acid perfusion is unknown. Possible sites include paracellular diffusion from the extracellular space, transapical secretion from S cells, or leaching from cells damaged by the perfusate. Antisecretin in the extracellular space and interstitium should reduce access due to paracellular diffusion from the interstitium without significantly affecting secretion or leaching. We therefore studied the effect of intravenous antisecretin antibody on luminal secretin output. Two groups of rabbits received either intravenous normal rabbit serum (controls) or antisecretin antibody, before perfusing a closed segment of duodenum with hydrochloric acid. Preliminary experiments established that duodenal perfusion with HCl concentrations below 0.025N produced no apparent mucosal damage on electron microscopy. HCl concentrations above this significantly damaged the mucosa. In the control group, perfusion with 0.01N, 0.0125N, and 0.025N hydrochloric acid resulted in a dose-dependent increase in secretin in the perfusate. Secretin output was markedly reduced in the group injected with secretin antibody. Antisecretin antibody significantly reduced bile flow at all levels of HCl concentration in the duodenal perfusate. These data suggest that luminal secretin is probably derived from the interstitium and travels to the lumen across narrow paracellular channels.
在酸灌注期间，免疫反应性促胰液素进入十二指肠腔的途径尚不清楚。可能的部位包括从细胞外间隙经细胞旁扩散、S细胞经顶端分泌，或从被灌注液损伤的细胞中渗出。细胞外间隙和间质中的抗促胰液素应会减少因从间质经细胞旁扩散而导致的进入，而不会显著影响分泌或渗出。因此，我们研究了静脉注射抗促胰液素抗体对腔内促胰液素输出的影响。两组兔子在向十二指肠的一个封闭段灌注盐酸之前，分别接受静脉注射正常兔血清（对照组）或抗促胰液素抗体。初步实验确定，用浓度低于0.025N的盐酸灌注十二指肠在电子显微镜下未产生明显的黏膜损伤。高于此浓度的盐酸会显著损伤黏膜。在对照组中，用0.01N、0.0125N和0.025N盐酸灌注导致灌注液中促胰液素呈剂量依赖性增加。注射促胰液素抗体的组中促胰液素输出明显减少。抗促胰液素抗体在十二指肠灌注液的所有盐酸浓度水平下均显著降低胆汁流量。这些数据表明，腔内促胰液素可能来源于间质，并通过狭窄的细胞旁通道进入肠腔。
