OPIOID RECEPTOR FUNCTION IN THE ENTERIC NERVOUS SYSTEM

描述：总体假设是μ阿片受体（莫尔） 内吞和再循环有助于确定豚鼠回肠肠道 神经元对内源性阿片样物质和生物碱有反应。 具体目的是：（1）将莫尔定位于肌间质的功能类型 神经元，描述了莫尔和脑啡肽之间的解剖关系 并确定脑啡肽的内源性释放是否能产生莫尔减少 胞吞作用，（2）描绘配体诱导的莫尔的细胞内途径 内吞作用，并确定它是否返回到表面，（3）确定 在莫尔内吞作用和 阿片样物质诱导的兴奋性肠神经传递减少， 通过肌肉抽搐的减少、ACh和SP的释放以及 使用LMMP制剂的SP内化，（4）检验假设， 莫尔内化改变阿片类药物对肠神经元的作用 受体内吞/再循环抑制剂和百日咳毒素， 抑制性G蛋白途径和测量 肌肉抽搐、ACh和SP释放及SP内化。 该项目将使用各种体内和体外制剂， 重点是光电子和共聚焦显微镜。 它将显示 免疫细胞化学法测定Mu阿片受体（莫尔）在兴奋性和 抑制性神经元，并确定莫尔 内吞作用和再循环利用多种组织学细胞发生， 标记物和药理学工具。 这份遗嘱的功能意义 通过将莫尔内吞作用与阿片样物质诱导的 兴奋性神经元的抑制和纵向的反应性 肌-肌间神经丛制剂。 这些研究将提供关于莫尔受体如何在 蠕动控制和细胞加工机制的莫尔在 对阿片配体的反应。 关于螯合和细胞的信息 对莫尔的处理将提供对受体机制的深入了解， 脱敏和最终下调。

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.