Abstract: ObjectiveTo study the effects of high temperature and LPS on IL-1 βmRNA expression in RAW 264.7 cells.MethodsMacrophage cell line RAW 264.7 in vitro was divided into 4 groups(control group of 37℃,LPSg roup of 37℃,control group of 40℃,LPS group of 40℃).The expression of IL-1β mRNA was detected with RT-PCR.ResultsThe IL-1β mRNA expression of RAW 264.7 cells was differen tunder the condition of 37℃ and 4℃ with or without LPS.The IL-1β mRNA expression of LPS group increased at 37℃;the blank group of 40℃ tended to ascend gradually while the LPS group of 40℃ ascended firstly but descended finally.ConclusionTemperature could affect the IL-1β mRNA expression in RAW 264.7 cells.High temperature and LPS co uld down-regulate IL-1β mRNA expression.