Background As an Ⅳ sedative, propofol (2,6-diisopropyl phenol) is widely used in clinical anesthesia while there is still debate on the effect of propofol on pain perception.The aim of this study is to clarify the role of propofol in control ling incisional pain and potential effect on the spinal opioids receptor expression.Methods Postoperative mode1 of nociception was established in male Sprague-Dawley rats weighing 200-250 g.Of which 96 rats were randomly assigned to 8 groups receiving operation with or without propofol.All drugs were ad ministered intravenously 5 rain before or after operation.The analgesic effects of systemic propofol were demonstra ted by the measurement of a cumulative pain score (CPS) based on the weight bearing behavior of the rats.After that, lumbar enlargement of the spinal cord was removed to evaluation of μ-opioid receptor (MOR) andδ-opioid re ceptor (DOR) mRNA expression by RT-PCR.