Abstract: Objective To investigate atorvastatin inhibits the proliferation and ptomotes apoptosis of VSMC bythe transcription factor AP1 in rats.Methods 80 rats were randomly divided into four groups: normal group,AS group, high-dose atorvastatin group (40mg/kg?d), low-dose atorvastatin group (10mg/kg?d).The VSMC apoptosis was detected by TUNEL assay.The protein expression level of AP1 andα-SM-actin were measured by immunohistochemical analysis and western blotting. Results TG、TC and LDL were significantly decreased in two atorvastatin groups (P<0.05). Atorvastatin significantly inhibited the VSMC proliferation and induced apoptosis (P<0.05). Atorvastatin regulated AP1 andα-SM-actin protein expression was significantly decreased(P<0.05).Conclusions Our results showed that the atorvastatin suppresses proliferation and promote apoptosis of VSMC through down-regulation of AP1 expression in rats.

Key words: Key words:atorvastatin , vascular smooth muscle cell, AP1, α-SM-actin