Parasagittal organization of the rat cerebellar cortex: Direct correlation between antigenic purkinje cell bands revealed by mabQ113 and the organization of the olivocerebellar projection

Abstract

The Purkinje cells of the cerebellar cortex and the cortical afferent and efferent projections are organized into parallel parasagittal zones. The parasagittal organization is clearly revealed by immunocytochemistry with a monoclonal antibody, mabQ113. The mabQ113 antigen is confined to a subset of Purkinje cells that are clustered together to form an elaborate, highly reproducible pattern of bands and patches, interspersed with similar mabQ113- regions. The mabQ113+ territories have been classified into seven parasagittal bands (P1+-P7+) in each hemicerebellum. The degree of correspondence between the compartments revealed by the anterograde labeling of the olivocerebellar projection and by mabQ113 immunocytochemistry has been explored in the adult rat. Horseradish peroxide-wheat germ agglutinin conjugate was injected as an anterograde tracer into the inferior olivary complex. When the injection site did not encompass all the olive, an incomplete, patchy labeling of the molecular layer was seen in the cerebellar cortex. Labeled zones of the molecular layer were interrupted by unlabeled regions to give a pattern of parasagittal cortical bands. The positions of these bands were compared with the distribution of the mabQ113+ antigenic bands as seen on the two adjacent sections. Labeled climbing fibers were found to terminate on both mabQ113+ and mabQ113- Purkinje cell zones. The mabQ113+/mabQ113- boundaries and the bands of climbing fibers seen by using the anterograde tracer typically coincide. The one consistent exception is the midline band of mabQ113+ Purkinje cells, P1+. The normal olivocerebellar projection is exclusively contralateral and the climbing fiber projection to the paramedian vermis splits P1+ down the middle, implying that it consists of two adjacent mabQ113+ bands not separated by mabQ113-territory. It is likely that the climbing fiber projection to the cerebellar cortex and the distribution of the two Purkinje cell phenotypes share a common compartmental organization.

Spatiotemporal Analysis of Purkinje Cell Degeneration Relative to Parasagittal Expression Domains in a Model of Neonatal Viral Infection

“…At PND28, PC loss in the cerebellar vermes of NBD rats was primarily confined to zebrin II/EAAT4-negative regions. Multifactorial processes are suggested to regulate pat- terned death of PCs, including energy failure, glutamate toxicity, climbing fiber-mediated excitotoxicity, and exclusive expression of other host proteins in PC subsets (e.g., p75, the low-affinity nerve growth factor receptor) (15,24,42,69,70,71,74,76). Viral transformation and viral infection can cause metabolic changes in infected cells, resulting in enhanced glucose uptake and glycolytic flux and in depletion of intracellular ATP (5,6,19,26,63,67).…”

Compartmentation in mammalian cerebellum: Zebrin II and P-path antibodies define three classes of sagittally organized bands of Purkinje cells.

“…In mammalian cerebellum, ZII antibody stains on each side of the midline, three bands in the vermis, one at the margin of the vermis and the hemisphere, and three in the hemisphere, separated by interbands of ZII-negative Purkinje cells. There is a close relationship between Zebrin compartments and the segregation of cerebellar afferent terminal fields (6,7). An identical periodic pattern is also revealed by using several other markers that subdivide the cerebellar cortex into two sets of modules-one corresponding to Zebrin-positive compartments and one corresponding to Zebrin-negative compartments (5,8,9 …”

Purkinje cell protein-2 regulatory regions and transgene expression in cerebellar compartments.

“…However, the parasagittal compartments observed in all B2-derived lines and in line A19~ persist in mature mice, reflecting stable cerebellar organization. Other markers (e.g., Zebrin I and II; Brochu et al 1990), as well as afferent and efferent projections (Gravel et al 1987;Boegman et al 1988), delineate cerebellar compartments. However, in contrast to the Purkinje cell populations expressing such endogenous genes, not all cells within each compartment express f~-galactosidase in transgenic mice.…”