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Lurcher mutant mice represent a model of olivocerebellar degeneration. They are used to investigate cerebellar functions, consequences of cerebellar degeneration and methods of therapy influencing them. The aim of the work was to assess the effect of foetal cerebellar graft transplantation, repeated enforced physical activity and the combination of both these types of treatment on motor skills, spontaneous motor activity and spatial learning ability in adult B6CBA Lurcher mice. Foetal cerebellar grafts were applied into the cerebellum of Lurchers in the form of solid tissue pieces. Enforced motor activity was realised through rotarod training. Motor functions were examined using bar, ladder and rotarod tests. Spatial learning was tested in the Morris water maze. Spontaneous motor activity in the open field was observed. The presence of the graft was examined histologically. Enforced physical activity led to moderate improvement of some motor skills and to a significant amelioration of spatial learning ability in Lurchers. The transplantation of cerebellar tissue did not influence motor functions significantly but led to an improvement of spatial learning ability. Mutual advancement of the effects of both types of treatment was not observed. Spontaneous motor activity was influenced neither by physical activity nor by the transplantation. Physical activity did not influence the graft survival and development. Because nerve sprouting and cell migration from the graft to the host cerebellum was poor, the functional effects of the graft should be explained with regard to its trophic influence rather than with any involvement of the grafted cells into neural circuitries.

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Lurcher mutant mice represent a model of olivocerebellar degeneration. They suffer from complete loss of Purkinje cells and a reduction of granule cells and inferior olive neurons. Their wild type littermates serve as healthy controls. The aim of the work was to compare solid embryonic cerebellar graft survival within a period of 9 weeks after their transplantation in adult Lurcher mutant and wild type mice of the B6CBA strain. The solid grafts were injected through a hole in the occipital bone. Host mice were sacrificed 3, 6, or 9 weeks after the transplantation and their cerebella and brain-stems were examined histologically to assess graft presence and structure. We did not find significant differences in graft survival rates between Lurcher mutant and wild type mice. The frequency of graft presence did not differ between mice examined 3, 6, and 9 weeks after the transplantation, neither in Lurchers nor in wild type mice. The grafts were of various sizes. In some cases, only small residua of the grafts were found. Nerve fiber sprouting and cell migration from the graft to the host tissue were observed more often in wild type mice than in Lurchers when examined 6 weeks after surgery. In the period 3-9 weeks after transplantation, massive dying out of the grafts was not observed despite regressive processes in some of the grafts. The degenerative changes in the Lurcher mutant cerebellum do not have strong impact on the fate of the solid cerebellar graft.