Effects of Buyang Huanwu decoction (BYHWD) on the change of oxygen free radical and cell ultrastructure were observed in rats with acute brain edema induced by pertussis vaccine (PV). The results showed that BYHWD could decrease significantly the contents of brain tissue protein and malondialdehyde, and raise the declining of superoxide dismutase and glutathione peroxidase activities. Also, BYHWD could reduce markedly the transport of pinosome in the left cerebral capillary endothelial cell, and lessen slightly the swelling of cerebral perivascular astrocyte processes and mitochondria in neuro...