Effects of Neural Stem Cell Transplantation on the Recovery of CNS Functions in Rats with Cortical Stroke

Ischemic stroke was modeled in white mongrel rats by removing surface vessels from the sensorimotor zone of the cortex. Preparations of neuron progenitor cells, i.e., rat embryo nervous tissue cells and human neural stem cells from the olfactory epithelium, and adult rat differentiated fibroblast preparations (cell controls) were transplanted at the perimeter of the area from which vessels were removed. Vital stainlabeled transplanted cells retained viability in the brain parenchyma for at least 16 days. Studies of impairments of the motor functions of the contralateral forepaw for eight weeks showed that only rats into which embryo nervous tissue was transplanted showed stable and significant (p < 0.05) improvements in performance in the cylinder test and the swimming test as compared with untreated animals and cell controls. The greatest differences in relative measures (efficacy) was 25% by the end of the experiment. There were no significant differences in the results of the whiskers test. This methodological approach expands studies of the mechanisms of the therapeutic actions of neural stem cells in stroke.