Neurological Disorders and Neurodegenerative Diseases

Parkinson's disease is characterized by a significant destruction of nigrostriatal dopaminergic neurons concomitantly with a loss of neurotensin receptors in neurons of the substantia nigra and the striatum. Neurotensin is a neuropeptide implicated in schizophrenia that specifically modulates neurotransmitter systems known to be dysregulated in this disorder. Modulation of neurotensin in the mesolimbic system is thought to underlie the mechanism of action of antipsychotic drugs. Indeed, several...

Receptors and Signal Transduction

The ACh receptors consist of two major groups the muscarinic and the nicotin-ic receptors. They can be distinguished by their selectivity to the alkaloids nicotine and muscarine. Dale originally introduced this classification in 1914 and it is still valid, in spite of the fact that several subtypes of nicotinic and muscarinic receptors have been described meanwhile. The nicotinic receptors belong to the ligand-gated ion channel superfamily. This comprises the nicotinic receptor (neuronal and...

Localization Within the Central Nervous System

TRH-immunoreactive cell bodies are distributed throughout the central nervous system. They are predominantly clustered in the olfactory bulbs, the cortex, the hippocampus, the amygdala and in the paraventricular nucleus of the hypothalamus. TRH-containing cells are also scattered in some further brain areas, including the neostriatum, the arcuate nucleus of the hypothalamus, the tubero-mammillary bodies, the reticular nucleus of the thalamus, the substantia nigra, the nucleus cuneatus and the...

Biosynthesis and Degradation

Proopiomelanocortin, its mRNA and the POMC gene are all highly conserved and, not surprisingly, the human POMC gene and, for instance, the POMC gene of the frog Xenopus laevis, as well as the corresponding mRNA, reveals considerable similarities. On the evidence of statistic phylogenetic analysis, the structure of the POMC gene has not varied during the past 350 million years of vertebrate evolution. However, some minor differences among species are evident. For instance, two biologically...

CB1 receptors

Cypin Guanine Deaminase Neurons

Genes encoding orthologs of the mammalian CB1 receptor have been identified in fishes, amphibians and birds, indicating that CB1 receptors may occur throughout the vertebrates. The genomes of the invertebrates Drosophila melano-gaster and Caenorhabditis elegans, however, do not contain CB1 orthologs, indicating that CB1-like cannabinoid receptors may have evolved after the divergence of deuterostomes and protostomes. The cDNA of the CB1-receptor is 5.7 kb in length and encodes for a putative...

Further Reading

Asan, E. 1997 Ultrastructural features of tyrosine-hydroxylase-immunoreactive afferents and their targets in the rat amygdala. Cell Tissue Res. 288 449-464. Bannon, M.J. 2005 The dopamine transporter role in neurotoxicity and human disease. Toxicol. Appl. Pharmacol. 204 355-360. Bell, C. 1989 Peripheral dopaminergic nerves. Pharmacol. Ther. 44 157-179. Betarbet, R., Sherer, T. B., Greenamyre, J.T. 2002 Animal models of Parkinson's disease. Bioessays 24 308-318. Bunzow, J.R., van Tol, H.H.,...