To provide a more comprehensive insight into the neuroprotective effects of GTPs on early brain ischemia, we examined the changes in TJ morphology, the mRNA and protein expression levels of claudin-5, occludin, ZO-1 and PKCα in microvessel fragments of cerebral ischemic tissue within 2 h of ischemia following the prophylactic neuroprotective treatment of GTPs. This evidence concerns the gene CLDN5 and brain ischemia.