Glutamate and GABA concentrations in the cerebellum of novel ataxic mutant Pogo mice

The Pogo mouse is an autosomal recessive ataxic mutant that arose spontaneously in the inbred KJR/MsKist strain derived originally from Korean wild mice. The ataxic phenotype is characterized by difficulty in maintaining posture and side to side stability, faulty coordination between limbs and trunk, and the consequent inability to walk straight. In the present study, the cerebellar concentrations of glutamate and GABA were analyzed, since glutamate is a most prevalent excitatory neurotransmitter whereas gammar-aminobutyric acid (GABA) is one of the most abundant inhibitory neurotransmitters, which may be the main neurotransmitters related with the ataxia and epilepsy. The concentration of glutamate of cerebellum decreased significantly in ataxic mutant Pogo mouse compared to those of control mouse. However, GABA concentration was not decrease. These results suggested that the decrease in glutamate concentration may contribute to ataxia in mutant Pogo mouse.

Differences of Zebrin II Expression Pattern Between Normal Balb/C and Ataxic Pogo Mouse Cerebellum / 대한해부학회지

The purpose of this study is to identify the differences of zebrin II expression between ataxic pogo and normal Balb/C mouse cerebellum. Zebrin II is expressed by subsets of Purkinje cells that form an array of parasagittal bands that extend rostrocaudally throughout the cerebellar cortex, separated by similar bands of Purkinje cells that do not express zebrin II. Zebrin II immunoreactivity was localized in the perikarya of Purkinje cells, and the dendrites. Distribution of zebrin II-immunoreactive Purkinje cells were very similar pattern in pogo and Balb/C mouse cerebellum. But, in the lobule III, distribution of zebrin II expression was different between pogo and Balb/C mouse cerebellum. In lobule III of Balb/c mouse cerebellum, 10~15 zebrin II-immunoreactive Purkinje cells were observed and clustered to form a parasagittal bands. On the other hand, zebrin II expressions of lobule III in pogo mouse cerebellum showed a little different patterns. In lobule III of pogo mouse cerebellum, three bilateral zebrin II immunoreactive parasagittal band were observed. P1 band was almost same with lobule III of Balb/C mouse cerebellum. But, P2 bands were composed of 50~60 Purkinje cells which were immunoreactive with zebrin II. These kind of thickening in zebrin II expression of pogo mouse cerebellum may be due to the genetical difference. Furthermore, these results may provide useful information with further ataxic pogo mice cerebellum studies.

Immunohistochemistry of Voltage-Gated Calcium Channel alpha1B Subunit in Mouse Cerebellum

Secretion of neurotransmitters is initiated by voltagegated calcium influx through presynaptic, voltage- gated N-type calcium channels. However, little is known about their cellular distribution in the mouse cerebellum. In the cerebellum, alpha1B immunoreactivity is found mainly on the cell bodies of all Purkinje cells. In addition, the immunoreactivity was detected on a subset of Purkinje cell dendrites, clustered to form a parasagittal array of bands. In the anterior lobe vermis, immunoreactive Purkinje cell dendrites form narrow stripes separated by broad bands of unstained dendrites. Moving caudally through the vermis, these stripes become thicker as a larger fraction of the Purkinje cell dendrites become immunoreactive. This localization study of the alpha1B pore-forming subunits in mouse cerebellum may guide future investigations of the role of calcium channels in neurological pathways.