RESUMO
OBJECTIVE: The aims of this study were to evaluate the efficiency of dexamethasone sodium phosphate (DSP) in the treatment of cold injury-induced brain edema and to compare systemic and topical application of DSP. METHODS: Sprague-Dawley rats weighing nearly 300 g were used in the experiments. Brain edema was formed by cold injury using metal sterile rods with a diameter of 4 mm that were previously cooled at -80 degrees C. Twenty-four hours after the injury, animals were decapitated and brain tissues were investigated by wet-dry weight method, lipid peroxidation ratio, and histological examination. RESULTS: The degree of edema was significantly lowered in groups in which DSP was administered using chitosan microspheres and by intraperitoneal route (P < .05). The statistical evaluation of the experimental results was performed using Mann-Whitney U test. Histological findings transmission electron microscopy (TEM) correlated with the quantitative results. CONCLUSION: Both intraperitoneal- and microsphere-administered DSP were found to be very effective in a cold injury brain edema model. The authors believe that future studies should lead to new applications of the microsphere formulations prepared by chitosan as the matrix material in many other therapies.