RESUMO
Objective To observe the effect of laser irradiation on the level of histamine (Hm) , 5- hydroxytryptamine(5-HT), interleukin-1 (IL-1), tumor necrosis factor α (TNF-α) in serum and β- endorphin (β- EP) in brain tissue in rat model of rheumatoid arthritis. Methods A total of 60 Wistar rats were randomly divided into four groups:a normal group, a model group (RA without treatment), a laser + drug treatment group (RA treated by laser and drug) and a drug treatment group (RA treated by drug alone). All the groups, except the normal one, were injected with complete Freund's adjuvant to make animal model of adjuvant arthritis. All the animals were then treated accordingly. The level of Hm, 5-HT, IL-1 and TNFα in serum and β-EP in brain tissue were measured. Results Laser downregulated the content of Hm, 5-HT, IL-1 and TNFα in serum and increased the content of β-EP in brain tissue. Conclusion Laser irradiation is an effective modality for treating the animal model of rheumatoid arthritis.