Abstract: Objective: To study the correlation between the Fg Bβ448 polymorphisms and their mRNA expression and fibrinogen(Fg) level, and the correlation between plasminogen activator inhibitor-1(PAI-1) 4G/5G polymorphisms and their mRNA expression and PAI-1 activity(PAI-1:A), PAI-1 antigen(PAI-1:Ag) level in patients with coronary heart disease(CHD). Methods: 　The subjects were divided into two groups: the control group and the CHD group. Contents of Fg(Clauss), PAI-1:A(Chromogenic assay) and PAI-1:Ag(ELISA) in the plasma were determined. PCR-RFLP was used to determine the Fg Bβ448 and the PAI-1 4G/5G polymorphisms, and RT-PCR was used to determine the expression of their mRNA. Results: This polymorphism is related to elevated Fg mRNA expression. The mRNA expression degree was as following: L/L genotype, the highest; A/L, the middle; and A/A, the lowest. There was a positive correlation between mRNA expression and plasma Fg level. The frequency of A/A genotype of Fg Bβ448 had no statistical difference between the CHD group and the control group (P＞0.05). Different genotypes offered different effects on PAI-1 mRNA expression. Expression of the 4G/4G genotype was in the highest, of the 4G/5G genotype was in the middle, and the 5G/5G genotype was the lowest. The frequency of the 4G/5G genotype of PAI-1 was significantly higher in the CHD group than that in the control group (P＜0.05), contributing to over-expression of PAI-1 mRNA. There was a positive correlation between mRNA expression and plasma PAI1:A and PAI-1:Ag level. Conclusions: Patients with CHD are hyper coagulation and fibrinolysis deficient, but elevated Fg may be related to the gene type and the environment. However, the environment may have an effect on the PAI-1 expression, but PAI-1 polymorphism is more important than the environment.

Key words: oronary arteriosclerosis, Heart diseases, Fibrinogen, Plasminogen activator inhibitor, Polymorphism