ILEOCECAL SPHINCTER REFLEX AND SPHINCTERIC PROPERTIES

该项目的长期目标是定义 回盲括约肌(ICS)对进食的贡献及测定 解剖ICS的不同成分对这些生理反应的反应。 这些研究将有助于理解 如果有的话，ICS在回肠和结肠功能之间的作用。该项目 将包括对麻醉猫的体内研究，在 记录腔内压和浆膜肌电活动。 同时和体外肌肉剥离研究，这也将允许 同时记录细胞外电活动和收缩 活动。在ICS看到的体内反应与 透壁刺激和静脉注射神经体液制剂及其应用 ICS肌条对这些相同刺激的体外反应。实验 将被设计用来确定这种差异的原因；确定 回肠盲肠结肠器的哪些特定部位 有助于生理和体内ICS反应；并确定 体内反应是否取决于回肠的综合反应， ICS和冒号。介导中枢神经系统反射的通路和神经递质 将研究回肠和结肠气囊扩张的反应。 使用神经毒素、肌瘤剔除技术和药物拮抗剂 经典的神经递质。此外，刺激计划的调解人 体外对透壁电刺激的松弛作用 调查过了。这些药物已经证明可以诱导ICS松弛 除了主要的候选人VIP外，还将研究 非胆碱能、非肾上腺素能神经的神经递质。这将是 通过快速反应检查的。推定的多肽 神经递质的作用将在体内和体外进行研究。 在ICS以及它们在调节胃回结肠中的可能作用 回应。

The long-term goal of this project is to define the physiologic response of the ileocecal sphincter (ICS) to feeding and to determine the contribution of various components of the anatomic ICS to these physiologic responses. These studies will contribute towards an understanding of the integrative role, if any, of the ICS between ileal and colonic function. The project will consist of in vivo studies on the anesthetized cat in which intraluminal pressures and serosal myoelectric activity are recorded simultaneously and in vitro muscle strip studies which will also allow the simultaneous recording of extracellular electrical activity and contractile activity. Discrepancy exists between in vivo responses seen at the ICS to transmural stimulation and to intravenous neurohumoral agents and the in vitro response of ICS muscle strips to these same stimuli. Experiments will be designed to determine the reason for such discrepancy; to determine which specific parts of the anatomic ileo-cecal-colonic apparatus contributes to the physiologic and in vivo ICS responses; and to determine whether in vivo responses depend on an integrated response of the ileum, ICS and colon. The pathway and neurotransmitters mediating the ICS reflex responses to ileal and colonic balloon distension will be investigated using neurotoxin, myomectomy techniques and pharmacologic antagonists of classical neurotransmitters. In addition, the mediator of the stimulus relaxation in vitro to transmural electrical stimulation will be investigated. Those agents already demonstrated to induce ICS relaxation will be studied in addition to VIP, the major candidate for the neurotransmitter in non-cholinergic, non-adrenergic nerves. This will be examined by means of tachyphylaxis. Peptides which are putative neurotransmitters will be investigated in vivo an in vitro for their action at the ICS and for their possible role in mediating the gastro-ileocolonic response.