Restorative Neurology and Neuroscience - Volume 4, issue 5

Authors: Isono, Mitsuo | Geller, Herbert M. | Poltorak, Maciej | Freed, William J.

Article Type: Research Article

Abstract: The A7 cell line is an astrocyte-like cell immortalized by SV40 large T antigen, using retroviral-mediated gene transfer. These cells were transplanted into rat brains, and the graft–host interaction was investigated immunohistochemically. The A7 cells survived focally 2, 6 and 8 weeks after transplantation and retained the immunocytochemical properties observed in vitro. No immunological response was observed. GAP-43 and N-cadherin immunoreactivities were not expressed by A7 cells, but were seen in the matrix within the area of the graft and in the surrounding brain tissue. This indicates that A7 cells may stimulate expression of GAP-43 and N-cadherin immunoreactivity by host …tissue. Expression of Thy 1.1 was not observed within the graft site after 2 weeks of survival, but 6 and 8 weeks after transplantation Thy 1.1 was observed within the graft area, indicating the possible co-existence of grafted cells and host tissue. Although indirect, these observations suggest that the A7 cells induce changes in host brain, including possible growth or regeneration of host tissue into the graft area. Show more

Keywords: Astrocyte, Immortalized cell line, Brain transplantation, Cell adhesion molecule, Immunological reaction

DOI: 10.3233/RNN-1992-4501

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 301-309, 1992

Authors: Tew, Elizabeth M.M. | Anderson, Patrick N. | Burnstock, Geoffrey

Article Type: Research Article

Abstract: Live or freeze-killed syngeneic adult muscularis externa, comprising myenteric plexus sandwiched between two layers of smooth muscle, was implanted into the corpus striatum of adult Fischer rats and examined electron microscopically 10 days to 6 weeks after operation. Living grafts contained healthy neurons and glial cells at all time-periods examined, although some areas of necrosis were observed. After 10 days, the glia limitans around the grafts were poorly developed and the adjacent brain tissue contained only a small number of small non-myelinated axons. After 3 and 6 weeks, the brain surrounding the living grafts contained many clusters of small non-myelinated …axons. Bundles of putative central nervous system (CNS) axonal sprouts had invaded the grafts, making contact with enteric glia, despite the presence of a well-developed glia limitans at the interface with the brain. In the longer-term grafts some CNS axonal sprouts in the myenteric plexus enlarged and became myelinated. A few astrocyte processes but no axons were found in the freeze-kilied grafts. The brain surrounding the freeze-killed grafts appeared to contain fewer axonal sprouts than were present around the living grafts. The possibility that the living grafts may promote both the sprouting and the elongation of CNS axons is discussed. Show more

Keywords: Myenteric plexus, CNS regeneration, Transplantation, Corpus striatum, Glia, Rat

DOI: 10.3233/RNN-1992-4502

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 311-321, 1992

Authors: Kataoka, Kazuo | Hayakawa, Toru | Mushiroi, Takeshi | Wakayama, Akatsuki | Yamada, Kazuo | Kuroda, Ryotaro | Ioku, Masahiko

Article Type: Research Article

Abstract: We compared the functional and anatomical alterations of somatosensory circuits in the acute (1–3 days after infarct) and chronic (3 months after infarct) stage after subcortical striatal infarct in Wistar rats. Occlusion of the left middle cerebral artery produced subcortical striatal infarct in approximately 69% of the rats. The others developed cortical infarct. The function of the somatosensory circuits was evaluated by [14 C]2-deoxyglucose autoradiography during physiological stimulation of the right vibrissae and face. In rats with subcortical infarct, the areas activated by sensory stimulation of the right vibrissae and face, applied 1 and 3 days after occlusion, were reduced …compared to sham-operated controls (P < 0.05). In the chronic stage of subcortical infarct, the areas of metabolic activation of the left anterior vibrissal and facial sensory area were increased compared to rats with acute subcortical infarct (P < 0.05). To evaluate the anatomical changes in the somatosensory pathway, at 1 day and 3 months after occlusion, we injected wheat germ agglutinin-horseradish peroxidase solution as an axonal transport substance bilaterally into the anterior vibrissal and facial sensory area. Tract tracing studies in both the acute and chronic stage of subcortical infarct showed a reduction in the peroxidase-positive area in the left thalamus compared to the control hemispheres (P < 0.01). The functional disturbance and recovery of the somatosensory circuits after subcortical infarct are discussed. Show more

Keywords: Local cerebral glucose utilization, Middle cerebral artery occlusion, Rat, Somatosensory circuit, Subcortical infarction

DOI: 10.3233/RNN-1992-4503

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 323-330, 1992

Authors: Ribarič, Samo | Stefanovska, Aneta | Vodovnik, Lojze | Cvirn, Pavel

Article Type: Research Article

Abstract: The purpose of this work was to examine whether, after sciatic axonotmesis, continuous low-amplitude direct current stimulation across the nerve crush lesion could affect the overall regeneration rate and shorten the time necessary to restore muscle force. Rats were randomly divided into cathode-stimulated (7 animals with a cathode stimulating electrode at the distal end of the nerve crush), anode-stimulated (6 animals with an anode stimulating electrode at the distal end of the nerve crush) and sham-treated (6 animals) groups. The recovery of muscle force was assessed by measuring the isometric tetanic contraction of the plantar flexor muscles once weekly, for …five weeks in all groups. There was no statistically significant difference (P > 0.05) among the three groups from the first to the third week after the nerve crush. The cathode-stimulated animals had a statistically significantly enhanced muscle force recovery in the fourth (P = 0.023) and fifth week (P = 0.003) after the nerve crush, when compared to the anode-stimulated and sham-treated groups. From the first to the fifth week after the nerve crush there was no statistically significant difference (P > 0.05) in muscle force between the anode-stimulated and sham groups. After axonotmesis, the average ratio of normalized muscle force to normalized body weight in the cathode-stimulated group reached the pre-crush control value in the fourth week following the nerve injury. This ratio was significantly lower all five weeks compared to the initial one before axonotmesis in anode-stimulated and sham-treated groups. Placing the cathode-stimulating electrode at the distal end of the nerve crush seems to have shortened the overall time of muscle force recovery. A possible mechanism for the enhancement of muscle force recovery in the cathode-stimulated group is proposed. Show more

Keywords: Electrical stimulation, Direct current, Implantable stimulator, Muscle force recovery, Nerve crush, Nerve stimulation

DOI: 10.3233/RNN-1992-4504

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 331-338, 1992

Authors: Molander, C. | Aldskogius, H.

Article Type: Research Article

Abstract: Clinical and experimental observations have demonstrated that peripheral nerve transection generally results in lasting disturbed sensory discrimination whereas nerve crush is followed by more or less complete functional restoration. This has been explained by an increased misdirection of regenerating fibers after transection as compared to crush injury. In the present study, sequential double-labeling was used to investigate the relative proportions of peripherally misdirected sensory fibers in the sural and tibial nerve branches after crush or transection of the parent sciatic nerve in the rat. Control experiments showed that 0.21% ± 0.12 (mean ± S.D.) of all labeled tibial and sural …neurons normally send axons to both nerves. After sciatic nerve crush or transection, 1.31% ± 0.78 and 3.79% ± 3.01, respectively, of all labeled tibial and sural axons were double-labeled indicating previously sural axons now having an axon in the tibial. Statistically significant differences in the percentages of bidirectional sciatic sensory neurons were found between the normal controls and after crush injury (P < 0.01) or transection injury (P < 0.001), respectively, but not between transection and crush (P > 0.05). The results indicate that the number of sensory neurons having an axon in two peripheral nerves is normally very small, that a substantial number of sensory axons become misdirected after both crush and transection with resuture, and that the number of misdirected fibers in the major sciatic branches after these types of injury is similar. Show more

Keywords: Nerve injury, Sensory axon, Fluorescent tracer, Sciatic nerve, Sensory dysfunction, Axonal sprouting, Double-labeling, Crush injury, Nerve transection

DOI: 10.3233/RNN-1992-4505

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 339-344, 1992

Authors: Cole, J.D. | Illis, L.S. | Sedgwick, E.M.

Article Type: Research Article

Abstract: Two cases are described in which spinal cord stimulation was effective in abolishing previously intractable deafferentation pain for a number of years, but in which late failure occurred for non-technical reasons. A possible explanation for this is advanced; namely that the dorsal column fibres have altered electrical properties due to a form of transganglionic degeneration.

Keywords: Post-amputation pain, Spinal cord stimulation, Transganglionic degeneration

DOI: 10.3233/RNN-1992-4506

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 345-347, 1992

Authors: Held, Jean

Article Type: Book Review

DOI: 10.3233/RNN-1992-4507

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 349-350, 1992

Article Type: Research Article

DOI: 10.3233/RNN-1992-4508

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 351-360, 1992

Article Type: Research Article

DOI: 10.3233/RNN-1992-4509

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 5, pp. 361-361, 1992