MOTILITY AND TRANSIT ACROSS THE ILEOCOLONIC JUNCTION

在这笔赠款的支持下，过去五年的工作使我们结束了 回结肠括约肌(ICS)，至少在狗和人身上，只是 控制运动和运输的几个要素之一 回结肠连接(ICJ)。机械因素，特别是 末端回肠与近端结肠的夹角也起作用； 但主要的控制机制存在于集成的，有时甚至是 回肠远端、ICS和近端结肠之间独特的运动模式。中的 在控制国际法院过境方面非常重要的特殊马达事件， 目前的计划已经确定了几个项目并确定了其特点。 这些症状包括：a)从末端移行的频繁回肠相爆发 回肠进入ICS；事实上，这些迁移性相性收缩构成 大部分阻力在ICS，b)回肠蠕动波(PPC‘s)，这些 是从回肠开始的强大的传播收缩，通过 IC，然后涉及不同长度的结肠，c)接受性松弛 在蠕动波之前的近端结肠，d)独特的回结肠 餐后后期，当食物残留物达到 区域。过去五年的工作也产生了几个强有力的新的 方法论，现已得到验证，可广泛应用。这些 包括a)双相(液体/固体)或双部位(胃-小肠和 节段性大肠)运输研究，通过这些研究，未准备的结肠可以 非侵入性研究，b)机电式稳压装置在 人和狗的结肠。因此，这项提案将解决 以下是具体目标： 1.确定结肠壁的紧张性变化在 国际法院对过境的控制；探索基调被 修改过的。 2.确定国际法院在食物时的特殊运动模式 残留物到达该区域；以确定这些马达的影响 交通模式；探索对这些运动的控制。 3.进一步确定回结肠运动障碍的作用和 在人类疾病中传播。 位于两段肠道之间的，这两段肠道在生理上和 在生态上不同的是，回结肠连接处对 通过优化膳食残留物在小肠中的滞留实现动态平衡 直到消化基本完成。相反，为了防止 细菌过度生长的有害影响，将回肠反流降至最低。 国际法院是肠道中最后一个需要详细研究的重要区域；它 已经被证明是直接临床的病理生理学的来源 关联性。这些都需要进一步调查。

The past five years' work supported by this grant have led us to conclude that the ileocolonic sphincter (ICS), at least in the dog and man, is only one of several elements that control motility and transit at the ileocolonic junction (ICJ). Mechanical factors, specifically the angulation of the terminal ileum upon the proximal colon, also contributes; but the major controlling mechanisms reside in the integrated and sometimes unique, motor patterns among distal ileum, ICS and proximal colon. Of the special motor events that are important in controlling transit at the ICJ, several have been identified and characterized by the current program. These include a) frequent ileal phasic bursts that migrate from terminal ileum into the ICS; indeed, these migrating phasic contractions constitute most the resistance at the ICS, b) ileal peristaltic waves ("PPC's"), these are powerful propagated contractions that begin in the ileum, pass through the ICS and then involve variable lengths of colon, c) receptive relaxation of the proximal colon, ahead of the peristaltic wave, d) unique ileocolonic motility in the late postprandial period, when food residue reaches the area. The past five years work has also yielded several powerful new methodologies, now validated to the point of broad application. These include, a) dual phase (liquid/solid) or dual site (gastric-small bowel and segmental large bowel) transit studies by which the unprepared colon can be studied noninvasively, b) application of the electromechanical barostat to the human and dog colons. Accordingly, this proposal will address the following Specific Aims: 1. To define the role of tonic changes in the wall of the colon in the control of transit at the ICJ; to explore mechanisms whereby tone is modified. 2. To define the patterns of specialized motility at the ICJ when food residue reaches the region; to determine the effects of these motor patterns on transit; to explore the control of these motilities. 3. To further establish the role of disordered ileocolonic motility and transit in human disease. Located between two segments of gut that are physiologically and ecologically distinct, the ileocolonic junction contributes importantly to homeostasis by optimizing retention of meal residues in the small bowel till digestion is largely complete. Conversely, to guard against the deleterious effects of bacterial overgrowth, coloileal reflux is minimized. The ICJ is the last important region of the gut to be studied in detail; it has proven to be the source of pathophysiologies of direct clinical relevance. These need to be further investigated.