BACKGROUND: Brain ischemia-reperfusion (IR) injury is closely connected with the activity of Kinesin. Previous research believes that reduced activity of Kinesin, a microtubule based motor protein, is an early mark for nerve cell death induced by brain ischemia. Erigeron breviscapus can prevent brain IR-induced proteinase C activation, reduce calcium overload, and reduce ischemic infarctional volume, thus attenuating brain IR injury. However, it still remains less reported at present whether the neuroprotective role of erigeron breviscapus is related to Kinesin activity.OBJECTIVE: To observe the effect of erigeron breviscapus on the activity of Kinesin, a microtubule based motor protein, in hippocampal pyramidal cells during brain IR.DESIGN: Randomized controlled study.SETTING: Anesthesia Department, Affiliated Hospital of Jining Medical College; Anesthesiology Key Laboratory, Affiliated Hospital of Xuzhou Medical College.MATERIALS: This experiment was carried out in the Anesthesiology Key Laboratory, the Affiliated Hospital of Xuzhou Medical College, between February and August 1999. Totally 35 male gerbils were included. METHODS: Gerbils were randomized into sham-operation group (n=5), ischemia-reperfusion control group (n=15) and erigeron breviscapus group (n=15), the latter two of which were further divided into three subgroups according to reperfusion time, namely reperfusion group Ⅰ (reperfusion of 6 hours), reperfusion group Ⅱ (reperfusion of 48 hours) and reperfusion group Ⅲ (reperfusion of 96 hours) with 5 in each subgroup. Gerbils in IR group and erigeron breviscapus group were subjected to IR model preparation before experiment by brain arterial occlusion for 10 minutes, while gerbils in sham-operation group had only bilateral common carotid artery isolated without occlusion.
Gerbils in erigeron breviscapus group were pretreated 15 minutes before ischemic inducement with intraperitoneal injection of breviscapine (its effective component is erigeron breviscapus) at a dosage of 45 mg/kg, which was replaced with the same volume of isometric normal saline in sham-operation group and IR group. IHC staining was used to detect hippocampus microtubule based motor protein-Kinesin activity with the assistance of computer imaging analysis technology.MAIN OUTCOME MEASURES: Activity and changes of Kinesin of animals in each group.RESULTS: Totally 35 animals were enrolled in this experiment and all entered the result analysis with no one lost during the experiment. In hippocampal CA1 region, Kinesin activity in IR group was found to descend to 58%, 38% and 12% respectively of that in sham-operation group at IR 6 hours, 48 and 96 hours (P < 0.01). In erigeron breviscapus group at IR 6 hours, 48 hours and 96 hours it was 81%, 61% and 21% of that in sham-operation group, and was obviously higher than that in IR control group (P < 0.05). However, the changes of Kinesin activity were not obviously different in hippocampal CA2, CA3 and CA4 regions.CONCLUSION: Erigeron breviscapus can exert brain-protecting function by reducing hippocampal CA1 Kinesin activity during brain IR injury.