REGULATION OF KININ DELIVERY ON HUVEC

构成这一提议基础的假设是， 血浆激肽原的内皮细胞受体是一种多聚体 结构，其命令接触蛋白酶原组装和激活 用于隔离的激肽释放的原激肽释放酶和其他激肽释放酶- 依赖的生物活动。激肽原表达，均高（HK） 这种受体上的低分子量（LK）激肽原允许激肽 [缓激肽（BK）和甲硫氨酸-赖氨酸-缓激肽（胰激肽）]被释放， 影响局部血管生物学。 这一假设是基于内皮细胞含有 几种膜表达的激肽原结合蛋白。第二，香港 和LK本身有多个绑定域，其特定的 定向至其内皮细胞结合位点，假定 受体。第三，HK作为内皮细胞结合位点， 前激肽释放酶第四，前激肽释放酶仅与内皮上的HK结合， 由内皮细胞激活，需要钙的金属蛋白酶， 动力学有利尿激酶原和随后的纤溶酶原 activation. 为了验证上述假设，本提案的具体目标如下： （1）内皮细胞上的激肽原受体将被激活， 测定(2)调节细胞释放激肽的机制- 将测定结合的激肽原。(3)序列的精细映射 对参与其与内皮细胞结合的激肽原的影响， 表征了 这些研究将描述激肽是如何从其 血管内室中的母体蛋白影响血管 生物学这些研究将提供一个新的途径， 缓激肽依赖性、内皮细胞活性如tPA释放， NO生成、cGMP升高、前列环素合成、超氧化物 形成和平滑肌超极化因子的产生。 缓激肽释放的调节在调节 冠状动脉、肾、肺和脑的局部血压 循环。

The hypothesis that forms the basis of this proposal is that the endothelial cell receptor for the plasma kininogens is a multimeric structure that orders contact protein zymogen assembly and activation of prokallikreins for sequestered kinin liberation and other kallikrein- dependent biologic activities. Expression of kininogens, both high (HK) and low (LK) molecular mass kininogens on this receptor permits kinins [bradykinin (BK) and met-lys-bradykinin (kallidin)] to be liberated to influence local vascular biology. This hypothesis is based upon the finding that endothelial cells contain several membrane-expressed kininogen binding proteins. Second, both HK and LK themselves have multiple binding-domains for its particular orientation onto its endothelial cell binding site(s), putative receptor(s). Third, HK serves as the endothelial cell binding site for prekallikrein. Fourth, prekallikrein only bound to HK on endothelium is activated by an endothelial cell, calcium requiring metalloprotease for kinetically favorable pro-urokinase and subsequent plasminogen activation. To test the above hypothesis, the specific aims of this proposal are as follows: (1) The kininogen receptor(s) on endothelial cells will be determined. (2) The mechanism(s) regulating kinin liberation from cell- bound kininogens will be determined. (3) The fine mapping of sequences on kininogens that participate in its binding to endothelium will be characterized. These investigations will characterize how kinins are liberated from its parent proteins in the intravascular compartment to influence vascular biology. These studies will provide a new avenue for modulation of all bradykinin-dependent, endothelial cell activities such as tPA liberation, NO formation, elevation of cGMP, prostacyclin synthesis, superoxide formation, and smooth muscle hyperpolarization factor production. Modulation of bradykinin liberation is important in the regulation of local blood pressure in coronary, renal, pulmonary, and cerebral circulations.