An ultrastructural study of granule cell/Purkinje cell synapses in tottering (tg/tg), leaner (tgla/tgla) and compound heterozygous tottering/leaner (tg/tgla) mice

摘要: Abstract Homozygous tottering ( tg / ) and compound heterozygous tottering/leaner la mutant mice exhibit juvenile onset of three abnormal neurological phenotypes: (i) petit mal -like epilepsy; (ii) ataxia; (iii) an intermittent myoclonus-like movement disorder. leaner early ataxia (postnatal days 10–12), also the disorder evidence absence seizure activity; is most evident in first month life, then diminishes severity frequency. The ultrastructure cerebellar molecular layer was examined adult (six to eight months) (20–25 days) all genotypes. In genotypes both ages, Purkinje cell dendritic spines were observed make multiple contacts with individual parallel fiber varicosities sections analysed. These synaptic units anterior posterior vermis hemispheres cerebellum, ranged from two nine spines/parallel varicosity. Occasionally, one postsynaptic belonged ectopic spine emerging proximal region a dendrite. This increase index some before symptoms disorders. highly suggestive that phenotype not primary cause synapsing single these mice, but on contrary, it could be ataxic symptoms.