Cerebellum cortex, nuclei

The 5-hydroxytryptamine receptor was immu-nolocalized in olfactory tubercle, piriform cortex, nucleus accumbens, island of Calleja, striatum, hippocampus (CAl and dentate gyrus) and the molecular layer of the cerebellum (Gerard et al. 1997). Specific binding of ( H]Ro 63-0563 [4-amino-N-2,6 bis-methylamino-pyridin-4-yl)-benzene sulphona-mide] to recombinant rat and human 5-hydroxy-tryptamine receptors was saturable, rapid, and reversible with equilibrium dissociation constants (Ka) of 6.8 nM and 4.96 nM, respectively (Boess etal. 1998). 

The effects of VIP and PACAP are mediated by three GPCR subtypes, VIP, VIP2, and PACAP receptor, coupled to the activation of adenjiate cyclase (54). The VIP subtype is localized ia the lung, Hver, and iatestiae, and the cortex, hippocampus, and olfactory bulb ia the CNS. The VIP2 receptor is most abundant ia the CNS, ia particular ia the thalamus, hippocampus, hypothalamus, and suprachiasmatic nucleus. PACAP receptors have a wide distribution ia the CNS with highest levels ia the olfactory bulb, the dentate gyms, and the cerebellum (84). The receptor is also present ia the pituitary. The VIP and PACAP receptors have been cloned. 

Localisation CA/S Hippocampus (CA1, CA3, DG), cortex, cerebellum (granular layer), olfactory bulb, habenula, spinal cord CA/S Caudate putamen, olfactory tubercle, nucleus accumbens, cortex, hippocampus (CA1, CA3, DG) CA/S Hippocampus (CA1, CA2), hypothalamus, thalamus, superior colliculus, raphe nuclei... 

FIGURE 29-1. Anatomy of the extrapyramidal system. The extrapyramidal motor system controls muscle movement through a system of pathways and nerve tracts that connect the cerebral cortex, basal ganglia, thalamus, cerebellum, reticular formation, and spinal neurons. Patients with Parkinson s disease have a loss of dopamine neurons in the substantia nigra in the brain stem that leads to depletion of dopamine in the corpus striatum. The corpus striatum is made up of the caudate nucleus and the lentiform nuclei that are made up of the putamen and the globus pallidus. 

Distribution Cerebellum, thalamus, hippocampus Cerebral cortex, striatum, nucleus accumbens Striatum, nucleus accumbens, cerebral cortex, substantia nigra Hippocampus... 

FIGURE 45-8 Tau protein immunoreactivity in brains and spinal cords from mice transgenic for mutant (P301S) human tau protein. (A, B) Cerebral cortex. (C) Amygdala. (D) Dentate nucleus of the cerebellum. (E, F) Brainstem. (G, H) Spinal cord. Scale bars (A-C, E, F), 40 pm (in A) (D, H) 60pm (in D) (G), 250pm. 

Figure 18.7 Distribution of iron in human brain. GP, globus pallidus SN, substantia nigra IPN, interpeduncular nucleus TH, thalamus DG, dentate gyrus RN, red nucleus CC, cerebral cortex HIPP, hippocampus CER, cerebellum FC, frontal cortex. (From Crichton and Ward, 2006. Reproduced with permission from John Wiley Sons., Inc.)...

CYP19 mRNA of adult Rhesus monkey is high in the bed nucleus of the stria terminalis > medial preoptic/anterior hypothalamus > amygdala intermediate in the medial basal hypothalamus > lateral preoptic/anterior hypothalamus and low In the septum > lateral-dorsal-medial hypothalamus undetectable in cingulate and parietal cortex, hippocampus, and cerebellum (Abdelgadir et al., 1997). 

CYP2E1 mRNA detected in cerebellum, frontal cortex, occipital cortex, pons, red nucleus, and substantia nigra of human brain by RT-PCR (Farin and Omiecinski, 1993). 

A global view of consciousness is that it is generated throughout the entire brain, as a result of synchronisation of relevant neural networks. Specific systems or regions—for example the cerebral cortex, brainstem reticular formation and thalamic nuclei—may be key anatomical integrators. Areas with the most widespread interconnections are pivotal, and on this basis the cortex and thalamus are more relevant than cerebellum and striatum for example. Frontal cortex for example connects with every other brain region, both in terms of input and output, with 80% of such connections accounted for by cortico-cortical connections. Thalamic intralaminar nuclei are, in conjunction with the reticular nucleus, reciprocally connected to all cortical areas. By contrast the cerebellum has very few output pathways and striatal-cortical input is (via the thalamus) confined to frontal lobe. 

The binding sites of TCAs in the brain appear to be localized to hypothalamus, frontal cortex, hippocampus, and caudate nucleus. Least binding is observed in the white matter and cerebellum (Langer et ah, 1981). 

HT3 receptors are located exclusively on neurons and are widely distributed throughout the peripheral and central nervous systems. In the periphery, 5-HT3 receptors are found on autonomic, sensory, and enteric neurons (Fozard 1984). In the central nervous system, 5-HT3 receptors are labeled in cortex, hippocampus, caudate hypothalamus, brain stem, midbrain, and cerebellum, with the highest density in discrete nuclei of the lower brain stem (e.g., dorsal vagal complex and spinal trigeminal nucleus), the area postrema, and substantia gelatinosa at all levels of the spinal cord (Palacios et al. 1991 Waeber et al. 1989). 

Noradrenergic neuromodulatory system. The neurons that synthesize norepinephrine (molecular structure in box) are located in several brainstem nuclei including the nucleus locus coeruleus, from which axons extend caudally (to the spinal cord), locally (to the brainstem and cerebellum), and rostrally (to the thalamus, subthalamus, limbic system, and to the cerebral cortex). Compare with figure 2.1 to identify structures shown. 

---