OPIOID RECEPTOR FUNCTION IN THE ENTERIC NERVOUS SYSTEM

描述：总体假设是Mu阿片受体(MOR) 内吞作用和循环有助于确定豚鼠回肠如何进入肠道 神经元对内源性阿片类药物和生物碱有反应。 其具体目的是(1)将MOR定位于肌肌的功能类型 神经元，描述吗啡和脑啡肽之间的解剖关系 并确定内源性脑啡肽释放是否能产生更多 内吞作用，(2)描述配体诱导的MOR的细胞内途径 内吞作用并确定其是否返回表面，(3)确定 是否存在时间和剂量相关的MOR内吞和 阿片类药物对兴奋性肠神经递质的抑制作用 以肌肉痉挛减少、ACh和SP释放及 P物质内化使用LMMP制剂，(4)检验假设 MOR内化改变阿片类药物对肠道神经元的影响 受体内吞/循环抑制物和百日咳毒素治疗 失活抑制性G蛋白通路并测定细胞数量的减少 肌肉抽动、ACh和SP释放及SP内化。 该项目将使用各种体内和体外制剂，其中 重点是光电子和共聚焦显微镜。它将显示 Mu阿片受体(MOR)在兴奋性和非兴奋性脑损伤中的免疫细胞化学定位 抑制性神经元，并确定MOR的细胞通路 吞噬和循环利用各种组织细胞 标志物和药理工具。这份遗嘱的功能意义 通过将吗啡内吞作用与阿片类药物诱导的相关性进行研究 兴奋性神经元的抑制与纵向刺激的反应性 肌肉-肌间神经丛制剂。 这些研究将提供有关MOR受体如何在 静脉曲张的蠕动控制及其细胞加工机制 对阿片配体的反应。关于隔离和蜂窝的信息 对MOR的处理将提供对受体机制的洞察 脱敏和最终的下调。

DESCRIPTION: The overall hypothesis is that mu opioid receptor (MOR) endocytosis and recycling helps determine how the guinea pig ileum enteric neurons respond to endogenous opioids and alkaloids. The specific aims are (1) to localize MOR in functional types of myenteric neurons, describe the anatomical relationship between MOR and enkephalins and determine whether endogenous release of enkephalins can produce MOR endocytosis, (2) delineate the intracellular pathway of ligand-induced MOR endocytosis and determine if it returns to the surface, (3) determine whether there is a temporal and dose correlation between MOR endocytosis and the opioid induced reduction in excitatory enteric neurotransmission as measured by the diminution of the muscle twitch, release of ACh and SP and SP internalization using LMMP preparation, (4) to test the hypothesis that MOR internalization alters the effect of opioids on enteric neurons by using inhibitors of receptor endocytosis/recycling and pertussis toxin to inactivate inhibitory G protein pathways and measuring the diminution of the muscle twitch, release of ACh and SP and SP internalization. The project will use a variety of in vivo and in vitro preparations, with an emphasis on light electron and confocal microscopy. It will show the location of mu opioid receptor (MOR) immunocytochemically in excitatory and inhibitory neurons, and determine the cellular pathways by which MOR endocytosis and recycling occurs using a variety of histological cellular markers and pharmacological tools. The functional significance of this will be investigated by correlating the MOR endocytosis with opioid-induced inhibition of excitatory neurons and the responsiveness of longitudinal muscle-myenteric plexus preparations. These studies will provide information on how MOR receptor plays a role in peristaltic control and the mechanisms of cellular processing of MOR in response to opioid ligands. Information on sequestration and cellular handling of the MOR will provide insight into mechanisms for receptor desensitization and eventual down-regulation.