METHYLENE DIANILINE TOXICITY TO BILIARY EPITHELIAL CELLS

亚甲基二苯胺（4，4 '-二氨基二苯基甲烷，DAPM）是一种化合物， 广泛用于环氧树脂和聚氨酯的生产， 目前用于制造诸如主动脉内球囊的物品， 人工透析机的管路。DAPM产生选择性毒性 胆管上皮细胞（BEC）的大鼠通过一个未知的机制。 以前的研究表明，低剂量DAPM改变BEC 线粒体超微结构和异常高水平的葡萄糖， 胆汁由于BEC负责从胆汁中吸收葡萄糖， 假设DAPM损伤表面葡萄糖受体和/或改变 高能磷酸盐代谢，调节ATP依赖性，Na+- 依赖性葡萄糖吸收 Aim 1将开发一种体外系统， 研究原代大鼠BEC。 将BEC分离并培养于 微载体珠至融合。 然后将微珠灌注到1 ml 柱以模拟体内条件。 该灌注系统将 提供1）对特定DAPM代谢物的作用的控制，2） 我们的目标人群的特异性，BEC和3）未来的模型 研究评估运输机制。目标2和3将使用此 系统，以评估DAPM及其代谢产物对 放射性糖的吸收依赖于葡萄糖受体， 线粒体损伤可能对葡萄糖产生后续影响 吸收 拟议的目标将进一步深入了解 DAPM诱导的损伤机制，以及有关 BEC中葡萄糖转运过程。

Methylene dianiline (4,4'-diaminodiphenylmethane, DAPM) is a compound widely used in the production of epoxy resins and polyurethanes which are currently used to make items such as intra-aortic balloons and tubing of artificial dialysis machines. DAPM produces selective toxicity to biliary epithelial cells (BEC) of rats by an unknown mechanism. Previous studies of low dose DAPM have shown alterations in BEC mitochondrial ultrastructure and abnormally high levels of glucose in bile. Because BECs are responsible for glucose absorption from bile, I hypothesize that DAPM damages surface glucose receptors and/or alters high energy phosphate metabolism which regulates ATP-dependent, Na+- dependent glucose absorption. Aim 1 will develop an in vitro system to study primary rat BECs. BECs will be isolated and cultured on microcarrier beads to confluency. Beads will then be perfused in 1 ml columns to simulate in vivo conditions. This perfusion system will provide 1) control over the effects Of specific DAPM metabolites, 2) specificity for our target population, BECs, and 3) a model for future studies to assess transport mechanisms. Aims 2 and 3 will use this system to assess the effects of DAPM and its metabolites on the absorption of radioactive sugars dependent on glucose receptors, and on mitochondrial injury which can have subsequent effects on glucose absorption. The proposed aims will provide further insight into the mechanisms of injury induced by DAPM, and specific knowledge regarding glucose transport processes in BEC.