The Relation Between Angiopoietin-1,Angiopoietin-2 And Coronary Collateral Circulation In CAD Patients

Background:Coronary collateral circulation(CCC) plays an importanty protective role in patients with severe coronary artery disease(CAD). Stimulation of coronary collateral artery formation by growth factors may be an attractive treatment for patients with CAD. Manys studies showed that angiopoietin-1(ANG-1) could stimulate coronary collateral artery formation and angiopoietin-2(ANG-2) might inhibit angiogenesis by inhibition of ANG-1.The present aims is to study is to explore the relation ship between serum ANG-1,ANG-2 levels and coronary collateral circulation.Methods:67 patients with severe coronary stenosis were included according to coronary angiography. Coronary collateral circulation(CCC) was graded by Rentrop Grading System into 4 degrees:degree0(n=22), degree1(n=17), degree2 (n=18), degree3(n=10). Serum concentrations of ANG-1,ANG-2 were analyzed by ELISA and the extent of coronary artery atherosclerosis was evaluated by Gensini's score system.Results:(1) Serum ANG-1 level in patients with CCC degree1 and 2 (644.2±63.2pg/ml)was significantly lower than that in CCC degree2 and 3 (1050.6±117.7pg/ml P<0.01).Serum ANG-2 level in patients with CCC degree2 and 3(522.6±88.lng/ml) was lower than in CCC degree0 and 1 (769.5±66.3ng/ml P<0.01).(2) A positive correlation was found between CCC degrees and serum ANG-1 (r=0.93),CCC was negatively correlated with Serum ANG-2 levels(r=-0.90). (3) Serum ANG-1 level was positively correlated with Gensini's score(P<0.01), and ANG-2 level has no correlation with Gensini's score(P>0.05).Conclusions:(1) with the degree of coronary collateral circulation increases, patients with severe coronary artery stenosis who increased serum concentrations of ANG-1, and degree of coronary collateral circulation was positively correlated, suggesting that ANG-1 may promote the formation of coronary collateral circulation. (2) with the degree of coronary collateral circulation increases, patients with severe coronary artery stenosis who decrease the concentration of ANG-2, and degrees of coronary collateral circulation was negatively correlated, suggesting that ANG-2 may inhibit the formation of coronary collateral circulation.