Experimental investigation on the prevention of delayed cerebral vasospasm with Tong Qiao Huo Xue Tang

Objective To investigate the prevention effects and the physicochemical mechanisms of action of Tong Qiao Huo Xue Tang on delayed cerebral vasospasm(DCD) after subarachnoid hemorrhage(SAH).Methods Macaca cynomolgus were divided into two groups and underwent craniectomy,a semipermeable microdialysis catheter was placed adjacent to right middle cerebral artery (MCA).Therapeutic group were exposed to Tong Qiao Huo Xue Tang and control group to placebo via oral .Results The diameter of proximal MCA in therapeutic group changed slightly on 7th day after operation(P >0.05),whereas it decreased prominently(P< 0.05) in control group with severe vasospasm.OxyHb concentration:There's no significant difference between the two groups on 2nd ～ 5th day(P >0.05),the concentration of therapeutic group(was zero after 8 days) was lower than that of control group (became zero after 12 days) on 6th ～ 8th day(P< 0.05).The peak value of therapeutic group (on 5th day) was lower than that of control group (on 7th day)(P< 0.05).Conclusion Tong Qiao Huo Xue Tang can prevent DCV after SAH effectively and decreasing OxyHb concentration around vessels after SAH maybe the mechanism.