Abstract: Abstract Objective: To investigate the mechanism of artherosclerosis by disfunction of vascular endothelial cell with hyperhomocysteinaemia , we observe the effects of homocysteine on the genetic expression of matrix metalloproteinase-1 in human vascular endothelial cell. Method: Incubate HUVEC CRL-1730(human umbilical vein vascular endothelia cell) in vitro with difference concentration (0、10、50、100、1000μmol/L) of homocysteine, then collecte cells in 1,6 and 24 hours after incubation. To semiquantitative the mRNA expression of MMP-1by RT-PCR(reverse transcription- polymerase chain reaction) method. Result: Homocysteine of pathology concentration (50-1000μmol/L) increased the expression of MMP-1 significantly in a dose-depended manner(p<0.05). Conclusion: Pathology concentration homocysteine change the expression of MMP-1 in vascular endothelial cell and up-regulated the expression of MMP-1 a dose-depended manner. So homocysteine effects on the genetic expression of matrix metalloproteinase-1 in human vascular endothelial cell and then promoted extracellular matrix degradation,induced artherosclerosis and plaque disruptive .

Key words: homocysteine, vascular endothelial cell, matrix metalloproteinase, genetic expression, extracellular matrix