[Nitric oxide promotes the differentiation of neural stem cells in vitro derived from the subventricular zone of neonatal rats].

OBJECTIVE: To observe the effect of nitric oxide (NO) on the differentiation of neural stem cells (NSCs) derived from subventricular zone (SVZ) of neonatal rats in vitro. METHODS: Conventional method was used to isolate and culture the NSCs from SVZ. Diethylenetriamine/NO(DETA/NO) was used as NO donor and Nitro-L-arginine methylester (L-NAME) was used as inhibitor of nitric oxide synthase (NOS). The immunofluorescence was used to identify the expression of nestin (a marker of NSCs), beta-III-tubulin (Tuj-1, a marker of neurons), glial fibrillary acidic protein (GFAP, a marker of astrocytes) and nNOS. The concentration of NO in medium was measured by Greiss assay. RESULTS: Cultured neurospheres were nestin-, BrdU- and nNOS-positive. After treatment with 40 micromol/L, 50 micromol/L and 60 micromol/L of DETA/NO for 5 days, the concentration of NO released was increased significantly (P < 0.01) as compared with that of the control group. The percentage of both differentiated neurons and astrocytes was increased significantly (P < 0.01 and P < 0.05) as compared with that of the control group. After treatment with 100 micromol/L, 150 micromol/L and 200 micromol/L of L-NAME for 5 days, the concentration of NO released was decreased as compared with that of the control group (P < 0.05). The percentage of both differentiated neurons and astrocytes were decreased as compared with that of the control group (P < 0.05). CONCLUSION: NO could directly promote the differentiation of NSCs derived from rat subventricular zone in vitro.