Purkinje cells dendritic tree

Fig. 13. Orthogonal arrangement of basket cell axons (thick horizonal fibers oriented in the plane of the Purkinje cells in A and B) and parallel fibers (thin, vertical fibers in A and B). A. Drawing from Golgi-impregnated section, Cajal (1911). B. Bodian-stained section of rat cerebellar cortex. Abbreviations A and B = stellate cells C = basket cell axon E = pericellular basket F = Purkinje cell dendritic tree G = climbing fiber Pb = pericellular baskets. Bar = 100 fim.

In the wri mutant, development of the Purkinje cell dentritic trees is impaired synaptic connections of parallel fibers on dendritic spines of Pukinje cells are decreased at two weeks of age, but by nine weeks malformed synaptic boutons lacking synaptic membrane specializations are significantly increased (Inoue et al.,... 

Fig. 4. Distributions of equivalent orders of primary (Va), secondary (Vb), and tertiary (Vc) vertices in control and 4% lead-exposed Purkinje cell dendritic networks. The frequency of secondary vertices relative to primary and tertiary vertices is increased in the lead-exposed animals, particularly over the lower order vertices (i.e., in the proximal portion of the tree), indicating an increase in the degree of collateral branching relative to symmetrical branching.

Figure 30-15 (A) Diagram of the two-dimensional tree formed by dendrites of a single Purkinje cell of the cerebellum. From Llinas.404 (B) Schematic diagram showing input and output pathways for Purkinje cells. (C) Recordings of output from four different neurons of the inferior olive. These action potentials are thought to arise from oscillations that arise within the neurons or within arrays of adjacent neurons coupled by electrical (gap junction) synapses. These oscillations synchronize the generation of action potentials so that some cells oscillate in synchrony while others (e.g., cell 4 above) do not. From McCormick.412...

The most significant of the abnormalities observed in a hypothyroid brain is a hypoplastic neuropile, i.e., a marked reduction in the number of connections between neurons [102], This has been observed both in the cerebrum and the cerebellum. For instance a permanent and dramatic reduction in the arborization of the dendritic tree of the Purkinje cell is observed in the hypothyroid cerebellum [103]. The length of the primary dendritic trunk is increased and a deficit in the number, density and branching of the dendritic spines is noticed. In contrast neonatal hyperthyroidism accelerates development of spines. Similar findings have been reported for the cerebrum, i.e., reduction in length and branching of pyramidal neurons, of the density of axonal terminals and of the number of spines [102],... 

The dendritic tree of the Purkinje cell is flattened in a plane perpendicular to the long... 

Purkinje cells. The recurrent collaterals extend into the molecular layer where they contact basket cells (O Donoghue et al., 1989). The whole collateral arborization is oriented perpendicular to the long axis of the folia, i.e. in the same plane as the dendritic tree of the Purkinje cell. In the cat it measures 300-700 //m in the sagittal and 100 00 m in the transverse direction (Bishop, 1988). The width of the arborization and its penetration in the molecular and granular layers varies for different parts of the cerebellum. Recurrent collaterals of Purkinje cell axons are constituents of the infra- and supraganglionic plexus. The main Purkinje cell axon enters and traverses the white matter to terminate on cells of the cerebellar or the vestibular nuclei. 

Fig. 27. Immunofluorescence localization of the cerebellar Ca -ATPase in a transverse cryosection of adult chicken cerebellum. CaS/Cl-IgG localizes the Ca -ATPase to the Purkinje cell bodies in the Purkinje layer (b), and the dendritic trees in the molecular layer (a). Very faint immunofluorescence was detected in the granule cell layer (c). Bar 50 m. Kaprielian et al. (1989).

Fig. 38. A. Nerve growth factor-R (NGF-R) transcripts are localized within Purkinje cells in the paraflocculus of rat cerebellum. B. NGF-R immunocytochemistry shows the perikarya of the Purkinje cells as well as the dense staining of the molecular layer, where the dendritic trees of the Purkinje cells arborize. Arrows in C and D point to parasagittal zones of intense labelling interdigitated with weaker labelling. Bar = 90 fim. Koh et al. (1989).

Figure 3. IniniMX)histoch0ndcal staining of 14 day old euthyroid ih,B) and hypothyroid (CrD) rat cerebellum with anti-Tau (A,C) and anti-MM>2 (B D) antibodies. Purkinje cell body (P) and their dendritic tree (D). Parallel fiber axons (A).

Tetradecanoylphorbol-13-acetate (150 nM) dramatically reduced the size of the dendritic tree of Purkinje cells from slice cultures of postnatal rat cerebellum, while the axonal projections of the Purkinje cells to the deep cerebellar nuclei appeared unaffected (Kapfhammer and Egle 1999). The protein kinase C inhibitor, GF 109203X (5 pM) increased both length and arborization of the dendrites. 

The expression of cGMP-specific phosphodiesterase (phosphodiesterase V) protein and mRNA in both the cell bodies and the dendritic tree of the Purkinje cells of the mouse was shown by Juilfs et al. (1999). 

Early postnatal exposure to MeHg seems to inhibit the development and maturation of the brain. Choi et al. (1981) observed incomplete arborization of the dendritic tree of Purkinje cells in mice exposed to MeHg in the early postnatal period. 

Berry, M. and Bradley, P. (1976) The growth of the dendritic trees of Purkinje cells in irradiated agranular cerebellar cortex. Brain Res. 116, 361-387. 

---