Clarification of organ specific transport mechanism of druge and its application to regulation of pharmacokinetics and pharmacodynamics

本研究的目的是从器官、细胞、分子和基因水平阐明药物的器官特异性转运，并开发新的药物药代动力学和药效学调控方法。本课题由14名研究者组成，经过两年的研究，取得了以下成果：1.获得了参与口腔和肠道吸收和分泌、肾分泌和重吸收、肝摄取和胆汁分泌以及脑内流和外流转运的转运蛋白的分子生物学特性的证据。对PepT 1、PepT 2、MCT 1、cMOAT、OAT-K1和OCT 2转运蛋白的克隆、转运功能和组织分布进行了研究。还阐明了P-糖蛋白作为亲脂性外源性物质在肠和血脑屏障（BBB）中的转运屏障。肽被证实是由吸附介导的内吞 ...更多信息 是在血脑屏障被输送到大脑。2.通过糖基化、跨集合淋巴结的内吞作用、离子电渗法和吸收促进剂打开紧密连接等方法来改善药物的吸收。3.肝细胞和枯否细胞对分级肝素的摄取被阐明为受清道夫受体介导和血浆蛋白介导机制的调节。利用半乳糖基化技术实现药物、蛋白质和基因的肝靶向转运。活性氧，如超氧化物和一氧化氮（NO），被阐明在各种疾病的发病机制中发挥关键作用。为了克服氧化应激，合成的定点SOD衍生物被成功地递送靶向细胞。利用“血管靶向”抗体识别肿瘤内皮细胞，为实体瘤的抗体治疗提供了一种有吸引力的方法。4.以α 1肾上腺素受体为模型，成功地克隆了受体，并检测了受体蛋白的组织定位。提示尿苷受体不仅在脑内，而且在外周组织中也有一定的作用。分析了大鼠服用哌唑辛后的药代动力学和药效学行为，包括脑内转运、受体结合和镇痛作用。少

The purpose of this research project is to clarify the organ specific transports of drugs from the view points of organ, cell, molecular and gene levels and to develop novel method for regulation of pharmacokinetics and pharmacodynamics of drugs. The following results were obtained by two years term of this research project consisted of 14 investigators :1.Several evidences were obtained for molecular and biological characteristics of transporters involved in the buccal and intestinal absorption and secretion, renal secretion and reabsorption, hepatic uptake and biliary secretion and in the brain influx and efflux transports. Cloning of transporters of PepT1, PepT2, MCT1, cMOAT,OAT-K1 and OCT2, their transport functions and tissue distribution were clarified. It was also clarified that P-glycoprotein functions as the transport barrier for lipophilic xenobiotics in the intestine and at the blood-brain barrier (BBB). Peptides were confirmed to be taken up by adsorptive-mediated endocytos … More is at the BBB to be delivered into the brain. 2.Improvement of absorption for drugs was achieved by glycosylation, endocytosis across Peyer's patches, iontophoretic method and by absorption enhancers to open tight junction. 3.Uptake of fractionated heparin by hepatocytes and Kupffer cells was clarified to be regulated by the scavenger receptor-mediated and plasma proteins-mediated mechanisms. Liver-specific delivery of drugs, proteins and gene was achieved by using galactosylated technology. Reactive oxygen species, such as superoxide and nitric oxide (NO), were clarified to play critical roles in the pathogenesis of various diseases. To overcome the oxidative stress, synthesized site-directed SOD derivatives were succeeded to deliver the targeting cells. An attractive approach for the antibody-based therapy of solid tumors was proposed and evaluated successfully by use of "vascular targeting" antibody to recognize tumor endothelial cells. 4.Using alpha 1-adrenoreceptor as a model, cloning of the receptors and detection of the tissue localization of the receptor protein were succeeded. It was indicated that uridine receptor plays some role not only in brain but also in peripheral tissues. Pharmacokinetic and pharmacodynamic behaviors for the transport in the brain, receptor binding and analgesic action were analyzed after peptazocine administration in rats. Less