GM1 ganglioside treatment reduces visual deficits after graded crush of the rat optic nerve
| Autor: | Michal Schwartz, Revital Duvdevani, J. Sautter, Bernhard A. Sabel |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Nerve Crush
Action Potentials G(M1) Ganglioside Handling Psychological Retinal ganglion Brightness discrimination Discrimination Psychological Neurochemical Reference Values Orientation Animals Molecular Biology Loss function Ganglioside General Neuroscience Optic Nerve Rats Inbred Strains Rats Compound muscle action potential Electrophysiology Visual Perception Optic nerve Neurology (clinical) Psychology Neuroscience Photic Stimulation Developmental Biology |
| Zdroj: | Brain Research. 565:23-33 |
| ISSN: | 0006-8993 |
| Popis: | Despite numerous reports of beneficial effects of GM1 ganglioside treatment following brain lesions in animals, the underlying neurobiological mechanism of ganglioside-induced functional restoration is still unclear. In order to obtain a better insight into this question, we have made use of a newly developed animal model of brain injury that would potentially permit us to determine the causal relationships(s) among behavioral and neuroanatomical/neurochemical parameters of restoration of function. Following graded crush of the adult rat optic nerve, we have treated the rats with intraperitoncally injected gangliosides and studied the functional outcome with electrophysiological and behavioral parameters. The electrophysiological recprding of the compound action potential (CAP) from excised rat optic nerve revealed a significant loss of CAP throughout the first 2 weeks after the injury. However, when rats were treated daily for 7 days with GM1-gangliosides, the CAP measured 10 days after the crush was significantly larger compared to operated controls without treatment. Thus, GM1 appeared to be capable of delaying or partially preventing retinal ganglion cells or their axons from secondary degeneration. Loss of visual function was also evident on the behavioral level of analysis: when rats with unilateral optic nerve crush were evaluated in a visual orienting paradigm, the rats revealed deficits in their ability to orient towards small, moving visual stimuli. However, within about 2 weeks, the animals recovered spontaneously to near normal performance. Daily treatment with GM1-gangliosides was found to significantly improve outcome, largely due to a reduction of the immediate post-lesion deficit. In a second behavioral experiment we also created graded crush in rats bilaterally and evaluated the animals visual capacities in a two-choice brightness discrimination task. In this park, an initial loss of function was followed by recovery within about 2 weeks, but GM1 treatment was without beneficial effects in this paradigm. It is concluded that GM1 improves outcome after graded crush of the adult rat optic nerve, although it appears that improved function needs to be documented with sufficiently sensitive behavioral assays. |
| Databáze: | OpenAIRE |
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