[Therapeutic effects of chitosan/polyethylene glycols-succinate/mitomycin C film drug delivery system on epidural scarring tissues after laminectomy of SD rats].

OBJECTIVE

To investigate the therapeutic effect of the chitosan/polyethylene glycols-succinate/ mitomycin C (CH/PEG-SA/MMC) film on epidural scarring tissues.

METHODS

According to a specific proportion of respective materials, the film of CH/PEG-SA/MMC was developed under some condition. Thirty SD rats were selected and randomized into 6 groups with 5 rats in each group. A rat model of lumbar laminectomy was used. The amount of 20 mg of the CH film was implanted into the animals in group I, 20 mg of CH/PEG film in group II, 20 mg of CH/PEG-SA film in group III, 0.05 mg/mL of the MMC soaking for 5 minutes in group IV, 20 mg of CH/PEG-SA/MMC film in group V, and nothing was done in group VI. Specimens were harvested 4 weeks after the above procedures and were then subjected to immunohistochemical and histological examinations to compare their therapeutic effects on epidural cicatricial tissues.

RESULTS

All rats were in good conditions after operation, without gait abnormality, restlessness, infection and death. There was no significant difference among the 6 groups in the postoperative Rydell score (P < 0.05). The content of hydroxyproline in groups I, II, III, IV, V and VI was (0.570 8 +/- 0.345 0), (0.728 6 +/- 0.150 6), (0.553 4 +/- 0.122 3), (0.313 3 +/- 0.106 4), (0.261 9 +/- 0.102 1) and (1.020 1 +/- 0.120 6) microg/mg, respectively. There was a significant difference between groups IV, V and groups I, II, III (P < 0.05), and there was significant difference between group VI and the rest 5 groups (P < 0.05). According to the histological observation, group V had less collagenous fiber paralleling the dura mater, with few inflammatory cells infiltration, with few capillary vessels and no reaction of macrophages.

CONCLUSION

CH/PEG-SA/MMC films can effectively reduce the amount of Hyp in epidural scarring tissues after lumbar laminectomy and therefore is a good treating method in preventing scarring tissue adhesion.