权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Elucidation of the mechanism of essential hypertension making a transgenic mice made by putative kallikrein binding protein

阐明原发性高血压的机制，用假定的激肽释放酶结合蛋白制备转基因小鼠

基本信息

批准号：
05557054
负责人：
TOMITA Kimio
金额：
$ 6.08万
依托单位：
Kumamoto University (1995)Tokyo Medical and Dental University (1993-1994)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1995
项目状态：
已结题

项目摘要

Kallikrein is a key enzyme in the processing of kininogen to release kinins, which exert diuretic and natriuretic actions. The regulation of kallikrein activities is poorly understood. Recently, Chao et al have identified a tissue specific kallikrein-binding protein that inhibits kallikrein activity, in human and rat. The gene coding for kallikrein-binding protein of rat and mouse has been subsequently cloned. It is well known that the renal kallikrein-kinin system is depressed in essential hypertension. The presence of kallikrein-binding protein in the kidney has been suggested by Western blot and Northern blot analysis. We used reverse-transcription and polymerase chain reaction to detect the precise localization of kallikrein-binding protein along the nephron using the microdissection method. In SD rats, the most abundant signals were found in inner medullary collecting duct, with small amount in outer medullary collecting duct, proximal convoluted tubule, and glomerulus. Similar distribution was found in WKY,however, in SHR,only a small amount was detected in inner medullary collecting duct. The presence of kallikrein-binding protein in terminal segment of the nephron suggests the importance of this protein in the regulation of body fluid and probably blood pressure. To explore the role of this protein in the mechanism of essential hypertension, we further tried to make transgenic mice to over-express the kallikrein-binding protein. Now we are processing the isolation of full length gene and express it to mice.

激肽释放酶是激肽原加工释放激肽的关键酶，其发挥利尿和排钠作用。对激肽释放酶活性的调节知之甚少。最近，Chao等人已经在人和大鼠中鉴定了抑制激肽释放酶活性的组织特异性激肽释放酶结合蛋白。大鼠和小鼠的激肽释放酶结合蛋白的编码基因随后被克隆。众所周知，原发性高血压患者的肾脏激肽释放酶-激肽系统受到抑制。通过Western印迹和北方印迹分析表明肾脏中存在激肽释放酶结合蛋白。我们使用逆转录和聚合酶链反应，检测沿着肾单位使用显微切割方法的激肽释放酶结合蛋白的精确定位。在SD大鼠，内髓集合管信号最丰富，外髓集合管、近曲小管和肾小球信号较少。在WKY中也有类似的分布，而在SHR中，仅在内髓集合管中检测到少量。肾单位终末段存在激肽释放酶结合蛋白，提示该蛋白在体液调节和血压调节中的重要性。为了探讨该蛋白在原发性高血压发病机制中的作用，我们进一步尝试使激肽释放酶结合蛋白在转基因小鼠中过量表达。现在我们正在进行全长基因的分离并将其表达给小鼠。