Abstract: Objective To investigate the effect of melatonin on oxidative injury of rat carotid arteries after balloon injury. Methods Twenty male sprague-dawley rats were randomized into control, melatonin, smoking, and smoking plus melatonin. An established protocol of smoking was carried out. The carotid arteries were collected 7 days later. The average content of ROS was measured. And Western blot was used to detected the expression of NF-κB, MCP-1, VCAM-1 and ICAM-1. Results Smoking significantly induced the increase of ROS and the expression of NF-κB, MCP-1, VCAM-1 and ICAM-1 in rat carotid arteries. Moreover, cigarette smoke exposure inhibited the expression of eNOS. Melatonin minimized the effect resulted from smoking. Conclusions Melatonin may attenuate the the oxidative injury and the expression of inflammatory mediators in rat carotid arteries resulted from smoking.

Key words: melatonin, smoking, oxidative injury, carotid artery