RESUMO
Objective To study the mechanism of rat blood pressure lowered by SO2 and SO2 derivatives.Methods 6-Keto-PGF1? and TXB2 were determined by radioimmunoassay in the plasma and aorta tissue of rats.Results The 6-Keto increased significantly in the isolated aortic rings in all exposure groups except 8 mmol/L group.No change of TXB2 was observed in the rings in all exposure groups.Meanwhile,6-Keto/TXB2 ratios increased significantly at 2 mmol/L and 4 mmol/L.Compared with the control group,6-Keto level decreased significantly in the plasma of the rats exposed to SO2 at 14 mg/m3,28mg/m3 and 56 mg/m3,but the level of TXB2 increased significantly.6-Keto/TXB2 ratios decreased gradually with the increase of SO2 concentration.Conclusion PGI2 and TXA2 are possibly changed by SO2 and SO2 derivatives,which regulates partly rat blood pressure.