Urata H, Nishimura H, Ganten D, Arakawa K
Max-Delbrück-Centre for Molecular Medicine (MDC)., Department of Hypertension Research, Berlin-Buch, Germany.
Blood Press Suppl. 1996;2:22-8.
The tissue renin-angiotensin system plays an integral role in the homeostasis of blood pressure and in the pathogenesis of cardiovascular remodeling. These effects are primarily mediated through the paracrine and autocrine actions of locally produced angiotensin II (A II). It is generally accepted that the conversion of angiotension I to A II is mainly due to angiotensin-converting enzyme (ACE). However, there are several in vitro and in vivo reports of ACE-independent synthesis of A II in hypoxic and ischemic heart and blood vessels, which may also contribute to cardiovascular pathology. The differential cellular and regional expression of ACE and chymase in the human heart and blood vessels suggests distinct pathophysiologic roles for these two A II-forming enzymes. The study of different pathways involved in tissue A II formation, including that of ACE- and chymase-independent enzymes, will clarify their respective contribution to the pathophysiologic changes in cardiovascular diseases, and help in planning a more comprehensive clinical strategy. This report reviews the properties of human heart chymase, an A II-forming serine proteinase, and compares it with those of ACE.
组织肾素-血管紧张素系统在血压稳态及心血管重塑的发病机制中发挥着不可或缺的作用。这些作用主要通过局部产生的血管紧张素II（A II）的旁分泌和自分泌作用介导。一般认为，血管紧张素I转化为A II主要归因于血管紧张素转换酶（ACE）。然而，有若干体外和体内研究报告表明，在缺氧和缺血的心脏及血管中存在不依赖ACE合成A II的情况，这也可能导致心血管病理改变。人心脏和血管中ACE和糜酶的细胞及区域表达差异表明这两种生成A II的酶具有不同的病理生理作用。对组织A II形成所涉及的不同途径的研究，包括不依赖ACE和糜酶的酶的途径，将阐明它们各自对心血管疾病病理生理变化的贡献，并有助于制定更全面的临床策略。本报告综述了人心脏糜酶（一种生成A II的丝氨酸蛋白酶）的特性，并将其与ACE的特性进行了比较。
