隐静脉与胸廓内动脉中糜酶依赖性血管紧张素II的形成

Chymase-dependent angiotensin II formation in the saphenous vein versus the internal thoracic artery.

作者信息

Nishimoto M, Takai S, Sawada Y, Yuda A, Kondo K, Yamada M, Jin D, Sakaguchi M, Asada K, Sasaki S, Miyazaki M

机构信息

Department of Pharmacology and the Department of Thoracic and Cardiovascular Surgery, Osaka Medical College, 2-7 Daigaku-cho, Takatsuki City, Osaka, Japan.

出版信息

J Thorac Cardiovasc Surg. 2001 Apr;121(4):729-34. doi: 10.1067/mtc.2001.112467.

DOI:10.1067/mtc.2001.112467

PMID:11279415

Abstract

OBJECTIVES

The great saphenous vein graft is known to be less patent than the internal thoracic artery graft. Recently, we reported that chymase-dependent angiotensin II formation plays an important role in the development of intimal hyperplasia in dog grafted veins. In this study we investigated the levels of angiotensin II-forming enzymes, angiotensin-converting enzyme, and chymase in human saphenous veins and internal thoracic arteries.

METHODS

The saphenous vein and internal thoracic artery specimens were obtained from coronary artery bypass grafts of patients during surgical procedures (saphenous vein, n = 16; internal thoracic artery, n = 16). Activities of angiotensin-converting enzyme and chymase were determined by using the extract from the saphenous vein or internal thoracic artery. Sections of the saphenous vein or internal thoracic artery were stained with van Gieson's elastin stain and were immunostained with anti-human chymase antibody.

RESULTS

The activities of angiotensin-converting enzyme in the saphenous vein and internal thoracic artery were 0.34 +/- 0.12 and 0.32 +/- 0.17 mU/mg protein, respectively, and the difference was not significant. The chymase activity in the saphenous vein was significantly higher than that in the internal thoracic artery (saphenous vein, 10.1 +/- 0.81 mU/mg protein; internal thoracic artery, 6.21 +/- 1.86 mU/mg protein). Chymase-positive cells in the saphenous vein were located in both the media and adventitia, and those in the internal thoracic artery were located only in the adventitia. The number of chymase-positive cells in the saphenous vein was about 2.6 times that in the internal thoracic artery.

CONCLUSION

The chymase activity, but not the angiotensin-converting enzyme activity, was significantly higher in the saphenous vein, suggesting that the high levels of chymase activity may be related to the poorer performance of the saphenous vein for use as a bypass conduit.

摘要

目的

已知大隐静脉移植物的通畅性低于胸廓内动脉移植物。最近，我们报道了糜酶依赖性血管紧张素II的形成在犬移植静脉内膜增生的发展中起重要作用。在本研究中，我们调查了人隐静脉和胸廓内动脉中血管紧张素II形成酶、血管紧张素转换酶和糜酶的水平。

方法

在手术过程中从患者的冠状动脉旁路移植术中获取隐静脉和胸廓内动脉标本（隐静脉，n = 16；胸廓内动脉，n = 16）。使用隐静脉或胸廓内动脉的提取物测定血管紧张素转换酶和糜酶的活性。对隐静脉或胸廓内动脉切片进行弹力纤维染色和抗人糜酶抗体免疫染色。

结果

隐静脉和胸廓内动脉中血管紧张素转换酶的活性分别为0.34±0.12和0.32±0.17 mU/mg蛋白，差异不显著。隐静脉中的糜酶活性显著高于胸廓内动脉（隐静脉，10.1±0.81 mU/mg蛋白；胸廓内动脉，6.21±1.86 mU/mg蛋白）。隐静脉中的糜酶阳性细胞位于中膜和外膜，而胸廓内动脉中的仅位于外膜。隐静脉中糜酶阳性细胞的数量约为胸廓内动脉中的2.6倍。