ISSN:
1432-1106
Keywords:
6-OHDA lesion
;
Foetal ventral mesencephalic graft
;
L-DOPA and carbidopa
;
Parkinson's disease
;
Circling behaviour
;
Neural grafting
;
Gliosis
;
Rat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary In rats with a unilateral 6-OHDA lesion of the nigrostriatal pathway, foetal ventral mesencephalic grafts implanted into the 6-OHDA-lesioned striatum produced a reduction in apomorphine-induced contralateral rotation, and complete abolition of (+)-amphetamine-induced ipsilateral rotation. The graft-induced reduction of apomorphine and (+)-amphetamine-induced rotation was not affected by chronic 27 week administration of L-DOPA and carbidopa to rats receiving foetal grafts. TH-immunohistochemistry revealed 〉96% loss of dopamine cells in the substantia nigra ipsilateral to the 6-OHDA lesion in all animals, but cell loss in the ipsilateral ventral tegmental area was more variable (21–46% of the intact side). TH-positive cells in the intact substantia nigra and ventral tegmental area were not affected by chronic treatment with L-DOPA and carbidopa. In the lesioned striatum of rats receiving sham grafts, no TH-positive cells or fibres were seen. In the 6-OHDA-lesioned striatum of animals receiving foetal grafts, many TH-positive cells were seen in the grafts and chronic treatment with L-DOPA and carbidopa did not reduce cell survival. GFA-P immunohistochemistry revealed that a unilateral 6-OHDA lesion followed by a sham graft was not associated with a reactive gliosis reaction in the striatum at the time of study (38 weeks after lesion surgery and 30 weeks after sham-graft), and treatment of such rats with L-DOPA and carbidopa was also without effect on glia. In contrast there was a marked gliosis in the striatum surrounding foetal grafts which was unaffected by chronic treatment with L-DOPA and carbidopa. The grafts themselves were surrounded by a rim of glial cells, and the glial density within the grafts was higher in animals receiving chronic L-DOPA and carbidopa treatment. However, there was no obvious relationship between the number of TH-positive cells within the grafts, or graft volume, and glial cell density within the grafts. These results suggest that long-term treatment with L-DOPA and carbidopa does not impair either the behavioural recovery produced by foetal ventral mesencephalic grafts in rats or the long-term survival of grafts as revealed by TH-immunohistochemistry. The presence of a foetal graft is associated with a reactive gliosis in the implanted striatum, which was not altered by long-term treatment with L-DOPA and carbidopa. However such treatment did result in an increase in glial density within the grafts themselves.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02259108
Permalink
