异氟醚对新生鼠齿状回神经前体细胞发育动力学的影响

Effects of isoflurane on the developmental dynamics of neural progenitor cells in the dentate gyrus of neonatal rats

目的探讨异氟醚对新生鼠齿状回神经前体细胞发育动力学的影响。方法将出生7日龄(P7)SD大鼠随机分为两组:异氟醚组(I组,n=8)和对照组(C组,n=7)。I组吸入1.5%异氟醚维持4 h,C组只吸入室内空气4 h。两组P7大鼠分别在麻醉暴露前及结束后腹腔注射5-溴脱氧尿苷(BrdU,100 mg/kg)以标记海马齿状回的神经前体细胞及其子细胞,然后在暴露结束后1 w,利用BrdU和DCX(未成熟神经元标志物)或GFAP免疫荧光双标的方法观察两组齿状回神经前体细胞的迁移、分化及存活的情况。结果与C组比较,I组P7大鼠齿状回颗粒细胞层BrdU+细胞的数量减少(P<0.05)。两组齿状回新生细胞迁移至颗粒细胞层或门区的比例,以及分化为神经元或神经胶质细胞的比例均无统计学差异(P>0.05)。结论异氟醚能够减少新生鼠齿状回新生颗粒细胞的早期存活,但并不影响神经前体细胞的早期迁移及分化。

Objective To investigate the effects of isoflurane on the developmental dynamics of neural progenitor cells （NPCs） in the dentate gyrus of neonatal rats. Methods Postnatal day 7 （PT） SD rats were randomly divided into two groups： isoflurane group （group I, n=8） and control group（group C,n=7）. The rats in group I were anesthetized by spontaneously inhaling 1.5% isoflurane for 4 h,while the controls only breathed the room air for 4 h. All animals were intraperitoneally injected Bromodeoxyuridine （BrdU; 100 mg/kg）before the induction and after the conclusion of isoflurane exposure to label NPCs and their progeny in the dentate gyrus. At 1 week after exposure, double immunofluorescence for BrdU and DCX （a marker of immature neurons） or GFAP were used to assess the early migration, differentiation and survival of NPCs. Results Compared with group C, the number of BrdU＋ cells in group I was significantly decreased （P〈0.05）. There were no significant differences in the proportion of newborn ceils migrating to granular cell layer or hilus, or in the proportion of differentiated neural or glial cells between the two groups. （P〉0.05）. Conclusion Isoflurane reduces the early survival of newborn granular cells but has no effect on the early migration and differentiation of NPCs in the dentate gyrus of neonatal rats.