Route of human mesenchymal stem cells transplantation and gross pictures of mice brain after trypan blue injection. (A) 100 μL trypan blue was injected through foramen magnum into position of cerebellum in a wild-type mouse, which was immediately sacrificed for visual examination to determine target accuracy. Most of the areas staining by trypan blue were located at cerebellum, medulla and nearby regions. (B) hMSCs were injected intravenously via tail vein or intracranially through foramen magnum under anesthesia. hMSCs, human mesenchymal stem cells.