Reneland R, Lithell H
Department of Geriatrics, Kungsgärdets Hospital, Uppsala University, Sweden.
Scand J Clin Lab Invest. 1994 Apr;54(2):105-11. doi: 10.3109/00365519409086516.
The importance of skeletal muscle for human haemodynamics and metabolism makes it a suitable sample tissue for the measurement of angiotensin converting enzyme (ACE; EC 3.4.15.1). A study of serum and muscle angiotensin-converting enzyme was performed in 50 essential-hypertensive subjects. Muscle tissue was obtained from the vastus lateralis muscle by Bergström needle biopsies. The method used is a modification in Cushman's fluorometric assay for tissue angiotensin-converting enzyme. It utilized 5 mM hippuryl-histidyl-leucine as a synthetic substrate for a 60-min fixed-time incubation at 37 degrees C. The 0.25 ml incubation mixture consisted of 0.12 mM potassium phosphate buffer, pH 8.1, 300 mM NaCl, and 1 or 2 mg homogenized muscle tissue. The activity was found to have the properties previously reported for human ACE. The intra- and interassay coefficients of variation of the method were 13% and 21%, respectively, for the 1 mg incubation as assessed from internal controls (n = 20). the muscle ACE activity in the hypertensive subjects was 49 +/- 14 mU g-1 (mean +/- SD) with no difference between values for men and women. No correlation was found between muscle ACE activity and age, or between muscle and serum angiotensin-converting enzyme activity. We consider this assay a useful new tool for investigating the role of angiotensin-converting enzyme in the pathogenesis and treatment of hypertension, as it can be applied to patient materials.
骨骼肌对人体血液动力学和新陈代谢至关重要，这使其成为测量血管紧张素转换酶（ACE；EC 3.4.15.1）的合适样本组织。对50名原发性高血压患者进行了血清和肌肉血管紧张素转换酶的研究。通过Bergström针吸活检从股外侧肌获取肌肉组织。所采用的方法是对Cushman组织血管紧张素转换酶荧光测定法的一种改进。它使用5 mM马尿酰-组氨酰-亮氨酸作为合成底物，在37℃下孵育60分钟。0.25 ml孵育混合物由0.12 mM磷酸钾缓冲液（pH 8.1）、300 mM氯化钠和1或2 mg匀浆肌肉组织组成。发现该活性具有先前报道的人ACE的特性。根据内部对照（n = 20）评估，对于1 mg孵育量，该方法的批内和批间变异系数分别为13%和21%。高血压患者的肌肉ACE活性为49±14 mU g-1（平均值±标准差），男性和女性的值无差异。未发现肌肉ACE活性与年龄之间、肌肉和血清血管紧张素转换酶活性之间存在相关性。我们认为该测定法是研究血管紧张素转换酶在高血压发病机制和治疗中作用的一种有用新工具，因为它可应用于患者材料。
