KALLISTATIN IN HYPERTENSION

这项竞争性的更新申请将继续探索卡利斯他汀在高血压中的作用。 激肽释放酶抑制剂是本实验室首次发现的一种新的血浆丝氨酸蛋白酶抑制剂，是组织激肽释放酶结合蛋白。 在目前的资助期间，出现了许多重要的发现，支持这一假设，即激肽在血压和血管生物学的调节中发挥作用。 我们发现，kallistatin是一种有效的血管扩张剂，直接导致血压的短暂降低，血管舒张在隔离的主动脉环，和血管舒张的肾血管灌注大鼠肾脏。转基因小鼠过度表达激肽是肥胖的，体细胞基因传递的激肽导致显着和长期降低血压的自发性高血压大鼠。Kalistatin在球囊损伤大鼠动脉中的表达明显增加，外源性Kalistatin刺激原代培养的血管平滑肌细胞增殖，从而可能调节血管细胞的生长。 具体目标是：1）通过定点突变和结构域置换分析Kalistatin在血管细胞增殖和血管舒张中的结构和功能关系：2）鉴定、表征和克隆血管中新的Kalistatin结合蛋白; 3）用球囊分析激肽抑制素在血管细胞增殖和迁移中的作用-反义kallistatin基因转染和核酶抑制策略建立大鼠动脉损伤模型; 4）通过转染Kallistatin基因，研究Kallistatin在自发性高血压大鼠血压调节中的作用，（5）在高血压人群、患病同胞及家系中分析kallistatin基因启动子区的多态性，并探讨kallistatin基因与高血压的遗传连锁关系。拟议的工作可以显着推进我们对激肽在血压调节和血管功能中的作用的理解，并可能为改善高血压和心血管疾病的检测和治疗提供新的工具和技术。

This competing renewal application will continue to explore the role of kallistatin in hypertension. Kallistatin was first discovered in our laboratory as tissue kallikrein-binding protein, a new plasma serine proteinase inhibitor. During the current funding period, many important findings have emerged in support of the hypothesis that kallistatin has a role in the regulation of blood pressure and vascular biology. We found that kallistatin is a potent vasodilator that directly causes a transient reduction of blood pressure, vasorelaxation in isolated aortic rings, and vasodilation of the renal vasculature in perfused rat kidney. Transgenic mice overexpressing kallistatin are hypotensive and somatic gene delivery of kallistatin caused a significant and prolonged reduction of blood pressure in spontaneously hypertensive rats. Kallistatin may regulate vascular cell growth, as its expression levels increase markedly in balloon-injured rat artery and exogenous kallistatin stimulates the proliferation of primary cultured vascular smooth muscle cells. The specific aims are: 1) to analyze structural and functional relationships of kallistatin on vascular cell proliferation and vasorelaxation by site-directed mutagenesis and domain substitutions; 2) To identify, characterize and clone new kallistatin-binding protein in blood vessels; 3) To analyze the role of kallistatin in vascular cell proliferation and migration with a balloon-injured rat artery model by antisense kallistatin gene delivery and by ribozyme inhibition strategy; 4) To study the role of kallistatin in blood pressure regulation by delivery of the kallistatin gene in spontaneously hypertensive rats, and 5) To analyze the promoter region of the kallistatin gene and genetic linkage and association between the human kallistatin gene and hypertension in selected hypertensive populations, affected siblings and family pedigrees. The proposed work could significantly advance our understanding of the role of kallistatin in blood pressure regulation and vascular function and may provide new tools and technologies for improved detection and treatment of hypertension and cardiovascular diseases.