RESUMO
The present study was to evaluate the effect of melatonin (MT) and EA on the cytotoxic activity of natural killer (NK) cells, the dynamic changes of the induction of interleukin-2(IL-2) and the content of POMC-derived peptides, beta-endorphins (betaE) and ACTH in spleen lymphocytes and in plasma of traumatic rats. The results showed that intraperitioneal (i.p.) injection of MT was able to recover the lower levels of NK cell activity and the induction of IL-2 production; MT could also decrease the higher betaE and ACTH levels induced by trauma in spleen lymphocytes and plasma. EA needling of Zusanli (St.36) and Lanwei (Extra.37) points obviously improved the immunosuppression produced by trauma and antagonized the elevation of betaE and ACTH contents induced by trauma stress in spleen lymphocytes and plasma. MT + EA could further modulate the depressed immune function, and there was a significant difference compared with MT (i.p.) or EA alone. MT + EA group further decreased the betaE and ACTH contents in immune cells and plasma. Yet, the mechanisms of the attenuation of MT and EA on immunosuppression induced by trauma need further study.