The first two authors contributed equally to this report.
Lipopolysaccharide Intranigral Injection Induces Inflammatory Reaction and Damage in Nigrostriatal Dopaminergic System
Article first published online: 14 NOV 2002
Journal of Neurochemistry
Volume 70, Issue 4, pages 1584–1592, April 1998
How to Cite
Castaño, A., Herrera, A. J., Cano, J. and Machado, A. (1998), Lipopolysaccharide Intranigral Injection Induces Inflammatory Reaction and Damage in Nigrostriatal Dopaminergic System. Journal of Neurochemistry, 70: 1584–1592. doi: 10.1046/j.1471-4159.1998.70041584.x
- Issue published online: 14 NOV 2002
- Article first published online: 14 NOV 2002
- Received June 3, 1997; revised manuscript received October 29, 1997; accepted November 7, 1997.
- Substantia nigra;
- Parkinson's disease
Abstract: The pathogenesis of Parkinson's disease is still poorly understood. To address the hypothesis that immunemediated events, such as microglial activation, may be involved in the dopaminergic neurodegeneration, we have studied the effect that intranigral injection of the immunostimulant lipopolysaccharide has on monoaminergic neurotransmitters in rats. Activation of microglial cells, visualized by immunohistochemistry with a specific monoclonal antibody, was already obvious 2 days after injection. In relation to the biochemical parameters studied, we found a significant decrease of dopamine levels in both the substantia nigra and striatum up to at least 21 days after intranigral injection of lipopolysaccharide. This result was supported by the decrease in tyrosine hydroxylase activity and the loss of tyrosine hydroxylase-positive neuronal bodies, shown by immunohistochemistry. These alterations of the dopaminergic system did not reverse during the interval studied (21 days); conversely, the serotoninergic system suffered only transient damage. In addition, we found that the neurotoxic effect of lipopolysaccharide was not mediated by nitric oxide. Based on our results we suggest that the nigrostriatal dopaminergic system is susceptible to damage by inflammatory events and that these may be implicated in neurodegeneration processes such as Parkinson's disease.