Objective: To observe the difference between borneol-induced opening of blood-brain barrier (BBB) and its pathological opening . Methods: The expression of inducible nitric oxide synthetase (iNOS) in brain microvascular endothelial cells in normal rats and brain-injury rats before and after treatment of borneol was examined by immunohistochemical methods with S-P staining and iNOS antibody. Results: iNOS expression was not different in normal rats before and after treatment. However, iNOS expression was inc...