Methylcobalamin, Folic Acid On Focal Cerebral Ischemia And Reperfusion Injury

Purpose: Cerebral ischemia would induce death and apoptosis of nerve cells,lose of neural sheath, which could lead brain disorder. In resent research,homocysteine(hcy) disease was considered as an independent risk factor forcerebral apoplexy. Hyc degree in the cerebral infarction patients was increased,and it had negative correlation from the degrees of folacin and mecobalamin.Folacin and mecobalamin could reduce Hcy degree in blood, increase theactivity of ERK. It could protect brain tissue. Other more, there have a lot ofreports demonstrate that mecobalamin could accelerate rehabilitation frominjured sheath of central nervous system , but the mechanism have somedisagree. In this study, we found brain tissue reperfusion model in order to studythe protect ability of folacin and mecobalamin in cerebral ischemia by measuringarea of cerebral infarction, apoptosis cells, Hcy amount in blood and evaluatingactivity of ERK before and after treating with folacin and mecobalamin. Method:We induced transient middle cerebral artery occlusion using monofilament nylonsuture. 50 rats (200-300g) were randomly divided into several groups includingsham ischemia, ischemia, pretreated with folacin, pretreated with mecobalaminand pretreated with both.Found animal model: We used the monofilament occlusion method to foundanimal model. Anestesia was induced in rat with 10% chloral hydrate usingintraperitoneal injection. A surgical monofilament nylon suture was used to block the origin of the middle cerebral artery; 3 h later, animals were performed bywithdrawal of the suture. Animals were sacrificed at 3, 6, 24, 72 h after withdraw.Sham ischemia group was only exposed common carotid artery and crotch,never blocked middle cerebral artery. All animals were maintained rectaltemperature at 37℃with heating pad, growth separately. Animals frompretreated group were treated with one of folacin, mecobalamin or both byadministration by gavage as soon as wake up, which had done twice a day since4 weeks before.In this study, first we measured cerebral infarction area with the method:Animals were sacrificed at 3, 6, 24, 72 h after reperfusion. The brains wereremoved immediately sectioned coronally, stained with 2% TTC phosphatebuffer solution. Photos of every section were analysis with LUZEX-F imageanalysis software to measure the area of cerebral infarction. Second, measuredapoptosis cells: After slidedewaxing, ethanol hydration, adding TUNEL stainbuffer, DAB coloration, we selected 6 representative fields of vision in order tomeasure positive cells in 1 mm~2. Third, we measured Hcy amount in blood inseries moments. Forth, we used immunoblotting method to mesure the activity ofERK: The brains were removed and separated 100mg of hippocampal sulcus.After ultrasound smashing, centrifuge, incubating with oxide labeled secondantibody, exposing with X-ray film, quantification was done with the analysis ofdensitometric scan. Result: The area of cerebral infarction, the amount of apoptosis cells and theexpression of Hcy in the groups of pretreated with either of folacin andmecobalamin were significant lower than the ischemic group respectively(P＜0.05), and the expression of ERK was more (P＜0.05), the group of the folacincombien with mecobalamin displayed much more significant (P＜0.01).Conclusion: Folacin and mecobalamin could visibly reduce the ischemicinjury. Both of them could protect brain tissue and it could get better curacy byuse together.