AIM: To investigate the inhibited effect of Doxycycline on the infiltration of inflammatory cells in rat alkali burn corneas.

METHODS: Corneas of 32 SD rats were injured with 1mol/L NaOH, then divided into two groups: control and doxycycline-treated. All agents were administered topically 4 times daily. Slit-lamp microscope was performed and inflammatory index was calculated at 3, 7, 14 and 21 days after injury. Then 4 rats were randomly sacrificed and each cornea was divided into two parts, one for histopathology, the other for ICAM-1 ELISA assay.

RESULTS:In control group, the inflammatory index and the number of inflammatory cell was higher than the doxycycline-treated dramatically at all time points(P<0.05). Compared with control group, corneal ICAM-1 expression decreased significantly in doxycycline-treated group at all time points(P < 0.05).

CONCLUSION:Doxycycline may inhibit inflammatory cell infiltration by down-regulating ICAM-1 expression.