[Effect of vascular smooth muscle alpha-actin on cardiac allograft vasculopathy and fibrosis].
OBJECTIVE
To explore the effect of vascular smooth muscle alpha-actin(VSMA-alpha) on cardiac allograft vasculopathy and fibrosis.


METHODS
After heterotopic cardiac transplantation model was established, the rats were divided into an acute rejection group, a chronic rejection group, an isograft group, and a normal group. Van Gieson staining and Massonos trichrome staining were used to observe the cardiac allograft vasculopathy and fibrosis respectively, and immunohistochemical stainings were used to examine VSM-alpha expression.


RESULTS
The fibrosis score of the normal group, the isograft group, the acute rejection group and the chronic rejection group were 0.00+/-0.00, 0.63+/-0.52, 1.75+/-0.71, and 2.75+/-0.46, respectively. The fibrosis score of the chronic rejection group increased significantly as compared with that of the normal group and the isograft group (both P<0.01), the indexes of coronary arteries stenosis were 0.08+/-0.02, 0.09+/-0.04, 0.12+/-0.05, and 62.86+/-17.18, respectively. The stenosis index in the chronic rejection group increased significantly as compared with that of all the other groups (P<0.01).VSMA-alpha was abundant in the allograft myocardium in the chronic rejection group.


CONCLUSIONS
Reactivation of fetal structural genes of vascular smooth muscle alpha-actin and its ectopic expression is associated with the cardiac allograft vasculopathy and fibrosis.
Department of Cardiac Surgery, First Hospital of Tsinghua University, Beijing 100016, China. zhangmingkui001@yahoo.com.cn
Mingkui
M
Zhang
Jinfu
J
Yang
Jianguo
J
Hu
D000199:Actins / Q000096:biosynthesis*; D000818:Animals; D005355:Fibrosis / Q000378:metabolism; D006084:Graft Rejection / Q000378:metabolism* / Q000473:pathology; D016027:Heart Transplantation / Q000009:adverse effects*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar
D000199:Actins