ABSTRACT
Objective To explore the magnetic resonance imging tracking of superparamagnetic iron oxid(SPIO) labeled embryonic neural stem cells (NSCs) transplantation into corpus striatum of the focal cerebral ischemia(FCI) rats and the effects of learning and memory abilities.Methods NSCs of embryonic rat were cultured in vitro and labeled with Fe2O3-mediated by poly-L lysine (PLL), with Prussian blue staining to evaluate the labeling rate and Trypan blue staining to observe cell viability of NSCs. The rats were randomly divided into groups A (normal control),B (normal labeled NSCs implanted),C (cerebral ischemia),D( labeled NSCs implanted),E (unlabeled NSCs implanted)and F (inactivated labeled NSCs implanted).The FCI models were made in groups C, D, E, F.The labeled NSCs or unlabeled NSCs or inactivated labeled NSCs were stereotaxically injected into the left corpus striatum of groups B,D,E,F respectively. The abilities of learning and memory were measured by the Y-type electronical maze in groups A, C, D, E after 3 d,7 d,2,3,4 weeks of transplantation respectively. MRI scanning was performed to monitor the NSCs in groups B, D, F at corresponding time. After MRI, the rats were killed and undergone Prussian blue staining of the brain histological section to observe the distribution of implanted NSCs.Results The labeling efficiency rate and cell viability of Fe2O3-PLL labeled NSCs were almost 100% and 95% respectively. Compared with group C, the abilities of learning and memory were significantly improved at each time point after transplantation in groups D, E (all P