Neuronal signalling

Neuromuscular junction (NMJ) is the synapse or junction of the axon terminal of motoneurons with the highly excitable region of the muscle fibre s plasma membrane. Neuronal signals pass through the NMJ via the neurotransmitter ACh. Consequent initiation of action potentials across the muscle s cell surface ultimately causes the muscle contraction. 

Huang EJ, Reichardt LF (2003) Trk receptors roles in neuronal signal transduction. Ann Rev Biochem 72 609-642... 

Dajas-Bailador F, Wonnacott S (2004) Nicotinic acetylcholine receptors and the regulation of neuronal signalling. Trends Pharmacol Sci 25 317-324... 

Besides the clear role for chemokines in modulating recruitment of cells into the CNS in HIV infection, and the potential role for chemokines to directly modulate neuronal signaling, recent evidence has suggested a link between CNS chemokine expression and enhancement of excitotoxic injury through enhancement of glutamate... 

Meucci O, Fatatis A, Simen AA, BusheU TJ, Gray PW, MUler RJ (1998) Chemokines regulate hippocampal neuronal signaling and gpl20 neurotoxicity. Proc Natl Acad Sci USA 95(24) 14500-14505... 

Parpura V, Basarsky TA, Liu F, Jeftinija S, Haydon PG (1994) Glutamate-mediated astrocyte-neuron signalling. Nature 369 744-747... 

As discussed previously, the neurohypophysis has a direct anatomical connection to the hypothalamus. Therefore, the hypothalamus regulates the release of hormones from the neurohypophysis by way of neuronal signals. Action potentials generated by the neurosecretory cells originating in the hypothalamus are transmitted down the neuronal axons to the nerve terminals in the neurohypophysis and stimulate the release of the hormones into the blood. The tracts formed by these axons are referred to as hypothalamic-hypophyseal tracts (see Figure 10.2). The action potentials are initiated by various forms of sensory input to the hypothalamus. Specific forms of sensory input that regulate the release of ADH and oxytocin are described in subsequent sections in this chapter. 

The adenohypophysis does not have a direct anatomical connection with the hypothalamus therefore, regulation of hormone secretion by way of neuronal signals is not possible. Instead, these two structures are associated by a specialized circulatory system and the secretion of hormones from the adenohypophysis is regulated by hormonal signals from the hypothalamus (see Figure 10.2). Systemic arterial blood is directed first to the hypothalamus. The exchange of materials between the blood and the interstitial fluid of the hypothalamus takes place at the primary capillary plexus. The blood then flows to the adenohypophysis through the hypothalamic-hypophyseal portal veins. Portal veins are blood vessels that connect two capillary beds. The second capillary bed in this system is the secondary capillary plexus located in the adenohypophysis. 

Roy, D. Belsham, D. D. (2002). Melatonin receptor activation regulates GnRH gene expression and secretion in GT1-7 GnRH neurons. Signal transduction mechanisms. J. Biol. Chem. 277, 251-8. 

In this chapter, we provide a brief overview of voltage-gated calcium channel subtypes and function, with an emphasis on neuronal transmission. The structure and kinetics of calcium channels is an extensive field of study, and outstanding reviews have recently appeared [3,4]. This chapter is focused on the potential opportunities for small-molecule intervention in neuronal signaling via antagonism of voltage-gated calcium channel subtypes, with a brief review of the chemotypes that have been recently reported to modify channel function. 

Joseph JA, Shukitt-Hale B, Denisova NA, Bielinski D, Martin A, McEwen JJ and Bickford PC. 1999. Reversals of age-related declines in neuronal signal transduction, cognitive, and motor behavioral deficits with blueberry, spinach, or strawberry dietary supplementation. J Neurosci 19(18) 8114-8121. 

Fivaz, M. and Meyer, T. Specific localization and timing in neuronal signal transduction mediated by protein-lipid interactions. Neuron 40 319-330, 2003. 

Peptides play a role in the plurichemical coding of neuronal signals 329... 

Some members of this family have been shown to mediate the dephosphorylation of MAPKs under physiological conditions. Others dephosphorylate Cdc-2 and related CDKs. However, relatively little is known to date about the regional distribution of these dual-functioning phosphatases in the brain and the specific function these enzymes serve in the regulation of neuronal signal transduction. Considerable interest has focused on one particular MAPK phosphatase, which can be induced very rapidly, at the level of gene transcription, in target cells in response to cellular activation [44]. 

Bibb, J. A. Role of Cdk5 in neuronal signaling, plasticity, and drug abuse. Neurosignals 12 191-199,2003. 

Hatton, G. I. and Parpura, V. (eds) Glia-Neuronal Signaling. Boston Kluwer Academic Publishers, 2004. 

Slezak, M. and Pfrieger, F. W. Role of astrocytes in the formation, maturation and maintenance of synapses. In G. I. Hatton and V. Parpura (eds), Glia-Neuronal Signaling. Boston Kluwer Academic Publishers, 2004, pp. 417-435. 

Both excitatory and inhibitory neuronal signals utilize energy derived from metabolism 536... 

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