Restorative Neurology and Neuroscience - Volume 9, issue 1

Authors: Urabe, Tadahisa | Zhao, Qing | Lundborg, Göran | Danielsen, Nils

Article Type: Research Article

Abstract: The optimal time for nerve suture in transected rat sciatic nerve was investigated. The sciatic nerve on both side nerves were transected and repaired by an epineurial suture technique 0–28 days after nerve transection. The regeneration distance was measured by the sensory pinch reflex test 2–6 days after nerve repair. The initial delay period and the regeneration rate were calculated by using a new mathematical model. One day delayed repair was sufficient to reduce the initial delay period and the largest reduction on the initial delay period was observed in the three day delayed repair group. The initial delay period …was reduced to 0.87 days as compared to 2.31 days for nerves repaired immediately (controls). The seven day and ten day delayed repair had similar effects but they also showed a decrease of the regeneration rate. The regeneration rate was not affected except for these two time points. The results suggest that the repair delay period can influence the initial delay as well as the regeneration rate. In our model an optimal effect was achieved on both these measures with a one or three day delay between transection and repair. Show more

Keywords: Rat sciatic nerve, Nerve regeneration, Nerve degeneration, Nerve repair, Delayed repair, Schwann cell

DOI: 10.3233/RNN-1995-9101

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 1-5, 1995

Authors: Serfaty, C. | Soroker, N. | Glicksohn, J. | Sepkuti, J. | Myslobodsky, M.S.

Article Type: Research Article

Abstract: Experimental animals with large posterior-cortical lesions develop disturbances of visual perception and visually-guided behavior in the contralateral space, resembling the syndrome of unilateral spatial neglect (USN) in humans. The visuo-motor performance in the ignored space is recovered some time following additional lesion inflicted to the contralesional superior colliculus (SC) or section of the intercollicular pathways. Based on the model that explains this recovery by disinhibition of the ipsilesional SC (the ‘Sprague effect’) Posner and Rafal [37] proposed that ipsilesional monocular occlusion could possibly reduce the ‘tone’ of contralesional collicular neurons thereby removing an important contributor of hemineglect. A group of …twenty-six right-hemisphere-damaged patients with USN was given a cancellation task under binocular and monocular (left and right) viewing conditions. Thirteen patients showed amelioration of left hemineglect in conditions of left-monocular viewing, as compared to the baseline binocular state. Although this result superficially resembles the Sprague effect, two patients benefited from right-monocular viewing whereas eleven patients showed no significant change in either right or left viewing conditions. The possible role of structures mediating interocular differences in target detection in cases of right hemisphere damage is discussed. It is suggested that even if the Sprague effect contributes to the salubrious influence of monocular viewing it is hardly the single factor involved. Show more

Keywords: Hemispatial neglect, Sprague effect, Monocular viewing, Rehabilitation, Substantia nigra pars reticulata, Superior colliculi

DOI: 10.3233/RNN-1995-9102

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 7-13, 1995

Authors: Borlongan, Cesario V. | Cahill, David W. | Sanberg, Paul R.

Article Type: Research Article

Abstract: Animals with unilateral neurotoxic lesions in the striatum exhibit a stereotypical biased rotational behavior in response to dopamine agonists. We recently argued that the rotational test may be subject to sensitization effects of the drug. Accordingly, we proposed the drug-free elevated body swing test (EBST) as an alternative behavioral index of motor asymmetry in striatal lesioned animals. EBST involves elevating the animal from the ground by holding its tail and simply recording the number of swings to either side made by the animal over 30 s. We previously reported that Sprague–Dawley, male 8-week-old rats, intrastriatally lesioned with 500 nanomoles of …3-nitropropionic acid or 225 nanomoles of quinolinic acid, exhibit biased swing activity at 7, 14, 21 and 28 days post-lesion. In the present study, we extended the efficacy of the EBST in measuring the recovery of motor function following fetal striatal transplants. At 2 months post-lesion, lesioned animals which show 70% or higher biased swing activity were transplanted with rat fetal striatal lateral eminence (16-day-old gestational age). When tested in the EBST at 1 and 3 months post-transplant, these transplanted animals displayed normalization of the biased swing activity. In contrast, animals transplanted with medium alone continued to exhibit a biased swing activity. The present study thus extends our previous EBST data to include successful behavioral characterization by EBST of recovery of motor function in lesioned animals receiving fetal transplants. Show more

Keywords: Motor behavior asymmetry, Fetal transplants, Striatum, Quinolinic acid, 3-Nitropropionic acid, Huntington's disease

DOI: 10.3233/RNN-1995-9103

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 15-19, 1995

Authors: Wilms, Pascale | Bähr, Mathias

Article Type: Research Article

Abstract: We have recently shown that optic nerve transection is followed by a delayed appearance (7–14 days after lesion) of putative guidance activities for retinal axons in the superior colliculus (SC) of adult rats. In the present study we analysed with immunohistological methods whether there is a correlation between localized reactive changes in the cellular compartment of the SC after deafferentation and the reappearance of putative guidance activities. The optic nerve of adult female Sprague–Dawley rats was transected. After 1 day to 1 year the contralateral SC was sectioned sagitally and examined with antibodies directed against Vimentin and glial fibrillary acidic …protein (GFAP) to label astrocytes, myelin basic protein (MBP) to detect oligodendrocytes, OX-42 to stain microglia and SMI-31 to determine degeneration of afferent retinal ganglion cell axons. These stainings were performed in order to detect differences in the cellular composition of macro- and microglial cells between the anterior and posterior regions of the SC. All cell populations we examined in the SC showed reactive changes after optic nerve transection. Microglia activation occurred as soon as 2 days after optic nerve transection in the anterior part of the SC. After 4 days, a homogeneous distribution of activated microglia was seen in the whole SC. GFAP upregulation occurred without a specific regional distribution. Only Vimentin-expressing astrocytes appeared with a delay of 1–2 weeks after deafferentation and were strongly restricted to the afferent optic tract and the very anterior region of the SC. In conclusion, a temporo-spatial correlation between the re-expression of guidance activities and changes in the cellular compartment of the SC exists in the delayed re-expression of Vimentin in astrocytes and their strong spatial restriction. Activated microglia might be involved in triggering regional changes in an anterior-posterior graded fashion in the deafferented SC. Show more

Keywords: Glial cells, Axotomy, Myelin basic protein, Regeneration, Visual system

DOI: 10.3233/RNN-1995-9104

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 21-34, 1995

Authors: Earl, Christopher D. | Kruk, Zygmunt L. | Bird, Margaret M.

Article Type: Research Article

Abstract: Roller tube cultures of foetal rat adrenal gland grown in the presence of nerve growth factor were implanted into the 6-hydroxydopamine-lesioned rat striatum to assess the ability of such cells to release catecholamine and restore function. Fast cyclic voltammetry was used to demonstrate that the lesions significantly reduced dopamine overflow following electrical stimulation of brain slices of the ipsilateral caudate putamen and nucleus accumbens. Viable reaggregates caused a significant reduction in the amphetamine-induced rotational behaviour over a period of 33 days, but no reduction of rotation was observed after the implantation of control materials. Fast cyclic voltammetry within and around …the site of the implant was unable to demonstrate electrically stimulated dopamine overflow. Transmission electron microscopy of sections taken from the lesioned and implanted striatum failed to demonstrate any transformation by the implants towards a neuronal phenotype. Show more

Keywords: Fast cyclic voltammetry, Brain slice, Foetal adrenal gland, Growth factors, Implantation, 6-Hydroxydopamine lesion, Tissue culture

DOI: 10.3233/RNN-1995-9105

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 35-42, 1995

Authors: Tsukada, Yasuzo

Article Type: Research Article

DOI: 10.3233/RNN-1995-9106

Citation: Restorative Neurology and Neuroscience, vol. 9, no. 1, pp. 43-63, 1995