[A new way for neural transplantation: the grafted central neurons migration from the subarachnoid space into the spinal cord and cerebral cortex].
In the studies of neural transplantation, Chen and his colleagues observed that the grafted central neurons could migrate from the subarachnoid space into the spinal cord and cerebral cortex. This finding promises an attractive possibility that a lot of neurons might be introduced into a long distance of the spinal cord and the extensive superficial layer of the brain which has suffered neuronal loss and thus might reinnervate a wide range of denervated area. Female rats were used in the study. Neural tissues or cell suspension containing fetal monoaminergic or arginine vasopressin (AVP) neurons were implanted into the subarachnoid space of the transected spinal cord or the normal brain and spinal cord. The rats were treated in different ways: some were grafted and the spinal cord was cut at the same time; grafted one month later or before the spinal cord was cut; grafted but the brain and spinal cord remained intact. Immunohistochemical method was used to monitor the grafted neurons after these rats survived for one or nine months. The results showed that there were a few to hundreds of 5-HT, TH or AVP-immunoreactive neurons and fibers found in the spinal cord or cerebral cortex near the grafted region. These neurons grew well and displayed their capacity of adaptability and long-time survival in the host CNS. No neurons, however, were found in the subarachnoid space of the grafted rats which had survived for another month or longer. On the other side, grafted with tissue block, it was found that transplants left in the grafted region grew as a "nodule" attaching to the surface of the spinal cord. The "nodule" was also found occasionally when the cell suspension was centered heavily at one region of the subarachnoid space. In both cases, the pia mater between them disappeared. Immunoreactive neurons were found in the "nodule" and neighboring spinal cord, some fibers from the neurons in the "nodule" extended into the spinal cord. It is supposed that a part of cells in the suspension died after grafted in the subarachnoid space and released hydrolases which injured the near pia mater by hydrolysis. As a result, some neurons in the suspension had a chance to migrate into the spinal cord and cerebral cortex. After the transplant in the subarachnoid space was gradually cleaned out, the enzymatic hydrolysis to the pia mater became weaker and finally stopped, the lesioned pia mater was gradually repaired. If the transplant was not cleared timely, the pia mater could not withstand the persistent hydrolysis and collapsed finally, leading the transplant to be fused with the host CNS.
Shu
J
J
Shanghai Institute of Physiology, Chinese Academy of Sciences, Shanghai 200031.
Chen
Z F
ZF
D000818:Animals; D001127:Arginine Vasopressin / Q000502:physiology; D015306:Biogenic Monoamines; D002465:Cell Movement; D002540:Cerebral Cortex / Q000166:cytology; D005260:Female; D009417:Nerve Tissue / Q000637:transplantation; D009474:Neurons / Q000637:transplantation*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013116:Spinal Cord / Q000166:cytology*; D013346:Subarachnoid Space / Q000601:surgery*; D014180:Transplantation / Q000379:methods
D015306:Biogenic Monoamines; D001127:Arginine Vasopressin