Alteration Of Substantia Nigra And Cornu Anterius Medullae Spinalis Structure In MPTP-induced Parkinson's Disease Model Mice

Objective:To observe alterations of cornu anterius medullae spinalis structure under the light microscope and glial fibrillary acid protein(GFAP)and cholinergic neurons of basal forebrain and ultrastructure under electronic microscope and explore the relationship between these alterations with age in 1-methyl-1-4-phenyl-1, 2,3,6-tetrahydropyridine(MPTP)-induced Parkinson's disease model mice.Methods:C57BL/6J mice(n=32)were divided into the following groups:PD model group of 8 weeks old,control group of 8 weeks old,PD model group of 30 weeks old,and control group of 30 weeks old.PD model mice were injected intrape- ritoneally with 30mg/kg MPTP each day for 5 consecutive days.Control mice were only injected with normal saline. Substantia nigra compact part(SNc)and basal forebrain and the cervical enlargement and intumescentia lumbalis of each mouse were taken out.The structure changes under the light microscope were observed by using toluidine blue staining.Immunohistochemical analyses were made on GFAP and ChAT. The ultrastructural changes of cornu anterius medullae spinalis were observed under electronic microscope.Results:Pathological changes of SNc and basal forebrain and cornu anterius medullae spinalis were found in the MPTP-injected mice model,which included neurons decreased notably(P＜0.01)and expression levels of GFAP increased significantly(P＜0.01)and that of ChAT decreased significantly(P＜0.01).Hydropic degeneration of neurons and apoptosis and oncosis could be found in general regions.Astrocytes were hyperplastia and hypertrophy.Meanwhile,gitter cells were activated.A serious of ultrastructural changes of permeability increase of blood-brain barrier of MPTP- injected mice existed.There were no position and age differences among these pathological changes.Ultrastructural image and expression levels of GFAP of control groups were normal.Conclusion:Pathological alteration of cornu anterius medullae spinalis may be one of the reasons and the structure basis for the dyskinesia in Parkinson's disease.The regions of Pathological changes of PD may be more widespread.