Investigation on mechanism of action of tissue TXA2 and PGI 2 on rabbits' brains after maxillofacial explosive injury

Objective: To detect the changes of TXA2 and PGI2 levels and discuss the significance of the level and ratio changes during maxillofacial blast injury. Methods: The maxillofacial blast injury model was made by standard spherical blast sources produced by NINT. Measure dynamics of blast wave to skin surface. The metabolites of thromboxane A 2(TXA2) and prostacyclin(PGI2), TXB2 and 6-keto-PGF1a, in cortex were examined before and 10min, 6h, 12h, 24h, 72h, 168h after injury by radioimmunoassay. Results: The pressure of central skin of blast injury was 335MPa, TXB2 and 6-keto-PGF 1 levels and the ratio augmented gradually after injury, and reached the peaks [(216.8 ± 22.5) pg/g and (102.9 ± 13.5) pg/g respectively] at the 24th hour, and reduced to the normal levels at the 7th day. Conclusions: The blast wave can injure the cortex and vessels, thus TXA 2 and PGI2 levels and the ratio increase, which aggravate injury of the cerebral cortex.