Cerebellum Purkinje cell

Cerebral cortex (layer I-VI, selected interneurons and principal cells) hippocampus (selected interneurons and principal cells) pallidum striatum (interneurons) thalamic relay nuclei olfactory bulb (mitral cells and interneurons) cerebellum (Purkinje cells and granule cells) deep cerebellar nuclei amygdala basal forebrain substantia nigra pars reticulata inferior colliculus brainstem... 

The normal cerebellar circuitry is illustrated and described in Fig. 1. In the present studies labeling of GAD mRNA was performed via in situ hybridization and quantified with the software program NIH Image J. The studies reported here focused on specific GABAergic neuronal types in the cerebellum Purkinje cells (PCs) in the... 

Neurons and glia exhibit a remarkable diversity of shapes. These different morphologies are so characteristic and distinctive that they have been used since the time of Cajal to define functional neural functions. For example, Purkinje cells in the cerebellum have such distinctive morphologies... 

Buffo, A., Zagrebelsky, M., Huber, A. B. et al. Application of neutralizing antibodies against NI-35/250 myelin-associated neurite growth inhibitory proteins to the adult rat cerebellum induces sprouting of uninjured Purkinje cell axons. /. Neurosci. 20 2275-2286, 2000. 

Both anandamide and 2-AG are inactivated by enzymatic hydrolysis (Goparaju et al. 1998). Fatty acid amide hydrolase (FAAH) is an enzyme that catalyses their hydrolysis. High concentrations of FAAH were found in the cerebellum, hippocampus and neocortex of rat brain, which are also rich in cannabinoid receptors. Further, there is a complementary pattern of distribution of FAAH and the CBl receptor. For example, in the cerebellum, FAAH is found in the cell bodies of Purkinje cells and the CBl receptor is found in the axons of granule cells and basket cells, which are presynaptic to Purkinje cells. 2-AG may also be inactivated by direct esterification into membrane phospholipids. Cannabinoid Receptors... 

CYPllBl mRNA in whole rat brain and hypothalamus by RT-PCR protein in cerebellum, especially Purkinje cells and hippocampus by IHC (Mackenzie et al., 2000). 

CYPl IB mRNA in frog telencephalon, diencephalon, midbrain, and cerebellum by RT-PCR. In situ hybridization shows CYPl IB mRNA in cells of pallium mediale in telencephalon, nucleus preopticus in diencephalon, stratum griseum superficiale tecti in midbrain, and Purkinje cells in cerebellum (Takase et al., 2002). 

CYP8A1 in neurons of bovine, rat and human brain, especially Purkinje cells of cerebellum and cortical neurons, but not glial cells by IHC (Mehl et al., 1999). CYP8A1 mRNA and protein in blood vessels of human brain, pyramidal cells of cortex and hippocampus, and Purkinje cells of cerebellum (Siegle et al., 2000). 0.000161 per GAPDH mRNA in whole adult human brain by RT-RT-PCR (Nishimura et al., 2003). 

RT-PCR, Southern blot, slot blot, immunobiot, and ICC reveal correlation of mRNA and CYP2D6 protein across 13 brain regions higher expression is seen in brains from alcoholics versus nonalcoholics. In hippocampus this was localized in CAl-3 pyramidal cells and dentate gyrus granular neurons. In cerebellum this was localized in Purkinje cells and their dendrites (Miksys et al., 2002). 

CYP2E1 mRNA seen in neurons of the cerebral cortex, Purkinje and granule cells of cerebellum, granule cells of dentate gyrus, and pyramidal neurons of CA1, CA2, and CA3 subfields of hippocampus in rat and human brain by in situ hybridization ethanol-induced brain expression in rat (Upadhya et al., 2000). 

IHC shows ethanol induction of CYP2E1 in olfactory bulbs, frontal cortex, hippocampus, and cerebellum of male rats nicotine induces in olfactory bulbs, frontal cortex, olfactory tubercle, cerebellum, and brainstem. More CYP2E1 found in brains from human alcoholics and alcoholic smokers in granular cells of the dentate gyrus, pyramidal cells of CA2 and CA3 hippocampus, and cerebellar Purkinje cells. More CYP2E1 In frontal cortices of alcoholic smokers versus all nonsmokers. CYP2E1 in cultured human neuroblastoma cells Induced by nicotine (Howard et al., 2003). 

The nervous system, a network of neurons in active communication, reaches its ultimate development in the 1.5 kg human brain.149 393 396 Many invertebrates, such as leeches,3963 crayfish, insects, and snails, have brains containing no more than 104 to 105 neurons,396b/397 398 but the human brain contains 10n. Each of these neurons interconnects through synapses with hundreds or thousands of other neurons. The number of connections is estimated to be as many as 60,000 with each Purkinje cell of the human cerebellum. There may be many more than 1014 synapses in the human brain.399 400... 

At the same time that the motor neurons send signals to the muscles, branches travel into other parts of the brain including the olivary nuclei, which send neurons into the cerebellum. The cerebellum acts as a kind of computer needed for fine tuning of the impulses to the muscles. Injury to the cerebellum leads to difficulty in finely coordinated motions. Input to the Purkinje cells arises from the climbing fibers, which originate in the inferior olive of the brain stem. Each climbing fiber activates a single Purkinje cell, but the dendrites of each Purkinje cell also form as many as 200,000 different synapses with parallel fibers that run across the cortex of the cerebellum (Fig. 30-15). 

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...

Staggerer Purkinje cell defect Vibrator Phosphatidylinositol transfer protein gene Tottering Mutation in voltage-gated Ca2+ channel Lurcher Abnormality in cerebellum Weaver Gly —> Ser mutation in K+ channel... 

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