 The study examined the effect of valproic acid, VPA, on regulated upon activation, normal T-cell expressed and secreted, ranties CCl5, and adhesion molecules in a rodent subarachnoid hemorrhage, SAH, model. VPA dose-dependently reduced the expression of ICAM-1, E-selectin, and ranties compared to the SAH group, and decreased CD45, plus, cells transmigrated to the vascular wall. The administration of CCl5 significantly reversed the inhibitory effect of VPA on CD45, plus, monocytes, E-selectin, and ICAM-1 level, suggesting that VPA attenuates SAH-induced adhesion molecules and neuro-information in a CCl5-dependent mechanism. This article was authored by Qi Zhenchang, Xu Chuan Wu, Qi Leng Lin, and others.