Restorative Neurology and Neuroscience - Volume 8, issue 4

Authors: Brailowsky, S. | Montiel, T. | Medina-Ceja, L.

Article Type: Research Article

Abstract: We studied the effects of two extracts of Ginkgo biloba, with and without terpenes, on motor recovery from cortical hemiplegia. Both extracts of the reference product (EGb761-IPSEN) produced a dose-dependent acceleration of behavioral recovery and diminished ventricular dilation in lesion rats. These results indicate that the active substance(s) participating in the beneficial effect of EGb761 is (are) contained in the non-terpenic fraction of the extract.

Keywords: Hemiplegia, GABA, Beam test, Plasticity, Coordinated walking, Treatment, Brain injury

DOI: 10.3233/RNN-1995-8401

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 163-167, 1995

Authors: Legendre, Diane I. | Vietje, Brad P. | Wells, Joseph

Article Type: Research Article

Abstract: Transplants of cell suspensions that were either selective for granule cells or contained all hippocampal cell types were placed in the hippocampal fissure or in the infragranular cleavage plane (IGCP) of the dentate gyrus. Several transplants were found in both areas in the same dentate gyrus. After a variety of post-transplant survival times, neurons of both the donor and the host were filled with lucifer yellow in fixed sections. Sections were also immunoreacted with antibodies to glial fibrillary acidic protein (GFAP), vimentin, neural cell adhesion molecule (NCAM and HNK-1/NCAM) and were histochemically reacted for ACHE. Dendrites of neurons from transplants …of cells of the whole hippocampus usually stayed within the transplant. If a dendrite from such transplants did grow out of the transplant, it grew into the molecular layer (ML) of the host dentate gyrus and not into the hilus of the host. Dendrites from granule cell selective transplants grew into the ML of the host and those that grew from fissure transplants were inverted from the normal orientation of host granule cell dendrites. Dendrites also grew out of the transplant in the absence of reactive gliosis. Transplants of cells from the whole hippocampus placed in the IGCP showed the greatest ingrowth of acetylcholinesterase (ACHE) fibers. In granule cell transplants made concurrently into the fissure and the IGCP, donor granule cell dendrites grew into the host ML from both sites, demonstrating that a gradient of tropic factors across the ML could not account for the direction and orientation of the dendritic outgrowth, since a gradient that directed the growth of one set of dendrites would work against the dendrites growing in the opposite direction. Show more

Keywords: Hippocampal transplant, Dendritic growth, Reactive astrocyte, ACHE, NCAM, Allograft, Gradient, Tropism

DOI: 10.3233/RNN-1995-8402

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 169-180, 1995

Authors: Kanje, Martin | Stenberg, Lena | Ahlin, Anette | Dahlin, Lars B.

Article Type: Research Article

Abstract: The presence of macrophages and the induction of c-jun protein and proliferation of non-neuronal cells were studied following implantation of silicone tubes with different diameters (i.e. 0.8 or 1.6 mm) around the rat sciatic nerve. Three days after implantation, numerous EDI and ED2 positive macrophages could be observed around the nerve beneath the 1.6 mm tubes. Some EDI and ED2 positive macrophages were also present in the endoneurium. In contrast, there were numerous EDI and ED2 positive macrophages in the endoneurium beneath the tube and distally in nerves surrounded by the 0.8 mm tube. In these experiments, there was also …a massive induction of c-jun protein and DNA synthesis in non-neuronal cells, as visualised by c-jun and BrdU antibodies respectively (e.g. a response similar to that observed after a crush lesion). Such activated cells, albeit few, were also present in the endoneurium beneath the tube of nerves with a 1.6 mm tube, but not distal to the tube in the endoneurium. At 7 days, the responses were somewhat amplified but essentially the same as at 3 days. The results showed that the large diameter implants, which do not cause axonal damage, as does the small diameter tube, but result in conditioning of the nerve [4], induced invasion of macrophages around the nerve and activation of some cells in the endoneurium beneath the tube. We suggest that cell activation is caused by factors released from macrophages and that endoneurial cell activation is important for the conditioning of the nerve by the silicone tube implant. Show more

Keywords: Nerve regeneration, Conditioning lesion, Macrophages, Transcription factors, c-jun, BrdU, Silicone, Nerve compression syndromes

DOI: 10.3233/RNN-1995-8403

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 181-187, 1995

Authors: Li, Gui Lin | Farooque, Mohammad | Holtz, Anders | Olsson, Yngve

Article Type: Research Article

Abstract: We evaluated, by irnmunohistochemistry, the changes of microtubule-associated protein 2 (MAP2) of rat spinal cord following compression injury of mild, moderate and severe degrees at the Th8–9 level. The spinal cord of normal rats and animals subjected to laminectomy only, presented immunoreactivity to MAP2 in nerve cell bodies and dendrites but not in axons and other structures. Following moderate and severe compression resulting in reversible paraparesis or irreversible paraplegia, respectively, the compressed segment showed loss of MAP2 immunoreactivity in dendrites and nerve cell bodies already 4 h after injury. This phenomenon remained throughout the experimental period of 9 days. …Our findings indicate that there is a rapid and long-lasting reduction of MAP2 in nerve cell bodies and dendrites of the compressed segment and that this alteration is related to the degree of the impact to the cord. The reduction of MAP2 may well have functional implications by interfering with neurotransmission. MAP2 immuno-staining is an excellent way of studying dendritic changes in spinal cord trauma and can be used in future experiments designed to investigate the influence of various therapeutic measures on secondary lesions after trauma. Show more

Keywords: Microtubule-associated protein 2, MAP2, Rat, Spinal cord, Trauma

DOI: 10.3233/RNN-1995-8404

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 189-197, 1995

Authors: Dahlin, Lars B. | Zhao, Qing | Bjursten, Lars M.

Article Type: Research Article

Abstract: Macrophages have been regarded as important sources for different growth stimulating factors in nerve regeneration. The distribution of macrophages in the fibrin matrix, which is formed between the proximal and distal nerve stumps in silicone tubes [29], was investigated in rats. The sciatic nerves of rats were transected and the stumps were introduced into a silicone tube. After 3, 6, 14 or 28 days, the distribution of macrophages (ED1 and ED2), the cytokine Interleukin-1β (IL-1β), fibrin/fibrinogen, fibronec-tin, neurofilament and 5-100 protein was investigated using immunocytochemistry. The pattern of fibrin/fibrinogen, fibronectin, neurofilament and 5-100 protein was similar to previously published data …[29]. The matrices at 3 and 6 days, as well as the later regenerate, contained both ED 1 and ED2 positive macrophages which was one of the cell types present. These cells were evenly distributed along the fibrin fibers or migrating cell columns. At the proximal and distal nerve stumps, macrophages were more abundant in the perineurial tissue which was close to the silicone tube, except for more macrophages in the distal part. IL-1β was also present, especially at 3 and 6 days and evenly distributed in the matrix, but the intensity of the staining decreased later. There was however no specific relation of ED1 or ED2 macrophage to the detected IL-1β. It is concluded that macrophages are trapped and present in the fibrin matrix formed between the proximal and distal nerve stumps at an early stage of the regeneration process and one of their products, IL-1β, was distributed in the matrix. Show more

Keywords: Nerve regeneration, Macrophages, Silicone, Matrix, Fibrin, Implants, Inflammatory cells, Cytokine

DOI: 10.3233/RNN-1995-8405

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 199-203, 1995

Authors: Saponjic, R.M. | Hoane, M.R. | Barbay, S. | Barth, T.M.

Article Type: Research Article

Abstract: Following brain injury there is an excessive release of excitatory neurotransmitters that may lead to secondary cell death. Although much research has focused on glutamate-NMDA receptor interactions, acetylcholine-muscarinic receptor interactions may also prove to be important for an understanding of the pathophysiological events that lead to secondary degeneration after brain damage. Previous experiments have shown that the muscarinic receptor antagonist scopolamine facilitates recovery from very transient (1 h—10 days) behavioral deficits after fluid percussion injury. The present study extends these findings by investigating whether scopolamine can facilitate recovery from the more enduring behavioral deficits (14–60 days) that follow electrolytic lesions …of the rat somatic sensorimotor cortex (SMC). Rats received unilateral lesions of the SMC and a regimen of scopolamine (1 mg/kg) or saline beginning 15 min after surgery. Following SMC lesions rats exhibited an impairment in placing the forelimb contralateral to the lesion as well as an ipsilateral somatosensory asymmetry on a bilateral tactile stimulation test. Rats treated with scopolamine showed a reduction in the initial magnitude of the contralateral placing deficit and an accelerated rate of recovery compared with saline-treated control rats. In contrast, scopolamine had no effect on recovery from the ipsilateral somatosensory asymmetry. These data are consistent with the idea that muscarinic receptor stimulation plays a role in the production of secondary brain damage, that blockade of this receptor leads to a facilitation of recovery on some behavioral tasks, and that electrolytic lesions may trigger some of the same posttraumatic events described in other models of neural trauma. Show more

Keywords: Forelimb-placing, Muscarinic receptor, Acetylcholine, Secondary brain damage

DOI: 10.3233/RNN-1995-8406

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 205-212, 1995

Article Type: Research Article

DOI: 10.3233/RNN-1995-8407

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 213-220, 1995

Article Type: Other

DOI: 10.3233/RNN-1995-8408

Citation: Restorative Neurology and Neuroscience, vol. 8, no. 4, pp. 221-223, 1995