Objective    To study the corre

lation between the levels of serum adiponectin (APN) and heme oxygenase-1 (HO-1) and the severity of coronary artery disease in the patients with acute coronary syndrome (ACS)

and investigate the interaction between APN and HO-1 in coronary heart disease.     Methods    One-hundred-and-sixty patients who had positive results in coronary angiography (CAG) were divided in an ACS group (

n

=92) and a stable angina pectoris (SAP) group (

n

=68) according to their medical histories and CAG results. In addition

fifty normal subjects who had negative results in CAG were involved as a control group. The patients were also divided in a one-branch group

a two-branch group

and a three-branch group according to the number of affected coronary branches

and in a ≥30 score group and a

<

30 score group based on the Gensini scoring system. The serum APN and HO-1 levels were measured by double-antibody sandwich ELISA in all the subjects. The correlation between the serum APN level and the serum HO-1 level

and that between the levels of serum APN and HO-1 and the severity of coronary artery disease were determined by comparison.     Results    The levels of serum APN and HO-1 were significantly lower in the ACS group and the SAP group than in the control group (5.84±2.29 and 8.01±2.04

vs

15.27±2.51 mg/L; 24.08±7.88 and  32.86±10.97

vs

54.35±14.8 μg/L). The larger the number of affected coronary branches

the lower the levels of serum APN and HO-1 (4.71±1.42 and 7.37±1.81

vs

9.23±1.76 mg/L; 20.17±6.53 and 29.35±5.72

vs

38.40±10.41 μg/L). The levels of serum APN and HO-1 were significantly lower in the ≥30 score group than in the

<

30 score group (5.75±2.28

vs

7.55±2.29 mg/L; 22.27±6.50

vs

32.38±10.60 μg/L). The serum APN level was positively correlated with the serum HO-1 level (

r

=0.598

P

<

0.01). The Gensini score was negatively correlated with the levels of serum APN and HO-1 (

r

=-0.576

P

<

0.01;

r

=-0.4

56

P

<

0.01).     Conclusion    The serum APN level is intimately and positively correlated with the serum HO-1 level. The levels of serum APN and HO-1 are negatively correlated with the severity of coronary artery disease. APN and HO-1 may interact in the development of coronary heart disease.