Effects of dexamethasone on the levels of IL-12 and IL-13 in bronchoalveolar lavage fluid and serum in rats

Objective To observe the effect of dexamethasone on the levels of IL-12 and IL-13 in bronchoaveolar lavage fluid(BALF) and serum in rats with Mycoplasma pneumoniae(MP) infection. To explore the mechanism of treatment MP pneumonia by dexamethasone. Methods A total of one hundred rats were randomly divided into four groups:azithromycin intervened group(n=25); dexamethasone intervened group(n=25); azithromycin and dexamethasone combination intervened group(n=25); control group(n=25). The rat model of MP pneumonia was established by dropping pneumonia bacterial liquid to its nasal cavity on day 0, 1, 2, and 3. Four groups received different interventions at the second day when the model was established successfully. Amounts of IL-12 and IL-13 in BALF and serum were measured by ELISA, the inflammatory infiltration of lung tissues was evaluated on day 3, 5 and 8. Results Compared with the control group, the expression of IL-12 and IL-13 in serum and BALF in azithromycin intervened group and combination intervened group had a significant difference(P0.05) on day 3, 5 and 8. Amount of IL-12 in serum in combination intervened group was higher than azithromycin intervened group on day 3, whereas IL-13 was lower than that in azithromycin intervened group(P0.05). Conclusions Dexamethasone can relieve inflammatory infiltration of lung tissues in rats.