叶酸对局灶性脑梗死大鼠神经干细胞增殖作用的影响

目的：探讨叶酸对局灶性脑梗死大鼠神经干细胞增殖作用的影响。方法：成年雄性SD大鼠40只随机分为假手术组（SO）、大脑中动脉栓塞模型组（MCAO）、缺血＋叶酸低剂量组（MCAO＋LFA）和缺血＋叶酸高剂量组（MCAO＋HFA）。通过叶酸灌胃给药28d。除假手术组外，其他3组采用线栓法制作大鼠大脑中动脉栓塞模型。叶酸补充前、后及制造模型后7d分别测定大鼠血清叶酸含量；采用免疫荧光双标记的方法检测各组大鼠脑缺血后脑组织BrdU＋Nestin免疫荧光双标阳性细胞密度。结果：补充叶酸后，与MCAO组相比，低、高剂量叶酸组大鼠的血清叶酸水平明显升高（P〈0．01），低、高剂量叶酸组大鼠脑组织BrdU＋Nestin免疫荧光双标阳性神经干细胞密度高于MCAO组（P〈0．01）。结论：通过灌胃补充叶酸能够提高大鼠血清叶酸水平，促进脑梗死大鼠神经干细胞的增殖，从而对局灶性脑梗死大鼠具有保护作用。

Effects of folic acid on proliferation of neural stem cells in rats with brain infarction

Objective： To observe the effect of folic acid on the proliferation of neural stem cells in the rats with brain infarction. Methods： 40 adult male Sprague-Dawley （SD） rats were randomly divided into sham operation group （SO）, middle cerebral artery occlusion group （MCAO）, MCAO＋low dose folio acid group （MCAO＋LFA） and MCAO＋high dose folic acid group （MCAO＋ HFA）. The cerebral ischemia model was induced by occlusion of middle cerebral artery after 28 d intragastric folic acid administration.Serum folie acid was measured with immune chemiluminescence before and 28 d after folio acid supplementation and 7 d after MCAO. The density of BrdU＋Nestin in brain was detected by immunohistochemistry. Results： Compared with the MCAO group and the SO group, the concentration of serum folic acid was higher in both MCAO＋LFA and MCAO＋HFA groups after folic acid supplementation （P〈0.01）. The density of BrdU＋ Nestin was significantly increased in the MCAO＋FA groups （P〈0.01）. Conclusion： Intragastric administration of folic acid can improve serum level of folic acid, enhance proliferation ability of neural stem cell in rats with cerebral infarction. Folic acid has protection effect on the rat with brain infarction.