Vertebrate, central nervous system

Category of glial cells in the vertebrate central nervous system with long radial processes. Astrocytes provide structural support to neive cells and help to control their chemical and ionic extracellular environment. 

The rate of synthesis is similar for trace amines and monoamine neurotransmitters, however, trace amines undergo a more rapid turnover due to their higher affinity to MAO and the lack of comparable cellular storage. Thus, the tissue concentration of trace amines in the vertebrate central nervous system is estimated to be in the range of 1-100 nM, depending on the trace amine and brain area, in contrast to micromolar concentrations of classic monoamine neurotransmitters. 

Collingridge, G. L. Lester, R. A. (1989). Excitatory amino acid receptors in the vertebrate central nervous system. Pharmacol Rev. 41, 143-210. 

Many lines of evidence. .. make it seem probable that GABA is a major inhibitory transmitter in the vertebrate central nervous system . 

Pasini, A. and Wilkinson, P.G., Stabilizing the regionalisation of the developing vertebrate central nervous system, Bioassays, 24, 427-438, 2002. 

Mayer ML, Westbrook GL. (1987). The physioiogy of excitatory amino acids in the vertebrate central nervous system. Prog Neurobioi. 28(3) 197-276. 

Development of the vertebrate central nervous systems is initiated during gastrulation through an... 

Holt CE, Gar lick N, Cornel E (1990) Lipofechon of cDNAs in the embryonic vertebrate central nervous system. Neuron 4 203—214. 

Van Harreveld, A., The extracellular space in the vertebrate central nervous system, in The Structure and Function of Nervous Tissue, Bourne, G. H., Ed., Academic Press, New York, 1972, 449. 

Another neurotransmitter system, that is a potential target for psychoactive drugs detected in the environment, is GABA, which is one of the most abundant neurotransmitters in the vertebrate central nervous system and is considered the main inhibitory neurotransmitter. Injections of GABA rapidly increased GTH-II release in goldfish by stimulation of GnRH release and inhibition of the inhibitory DA system66. 

Gamma-aminobutyric acid (GABA) is a widely distributed amino acid in the nervous tissue of both vertebrate and invertebrate organisms, where it functions predominantly as an inhibitory neurotransmitter (1,2). Receptor sites for GABA have been extensively studied in vertebrate central nervous systems (CNS), where there are at least... 

Nonchev, S., Maconochie, M., Gould, A., Morrison, A., Krumlauf, R. 1997. Cross-regulatory interactions between Hox genes and the control of segmental expression in the vertebrate central nervous system. Cold Spring Harb. Symp. Quant. Biol. 62, 313-323. 

Orbach, H.S., Cohen, L.B. Optical monitoring of activity from many areas of the in vitro and in vivo salamander olfactory bulb a new method for studying functional organization in the vertebrate central nervous system. J. Neurosci. 3, 2251-2262 (1983)... 

A fundamental characteristic of the vertebrate central nervous system (CNS) is bilateral symmetry along the midline (Figure 3). This symmetrical structure divides neuronal projections into two types, uncrossed projections to ipsilateral targets and crossed projections to contralateral targets. Over the past decade, the mechanism involved in the formation of crossed projections has been extensively studied in spinal cord commissural projections. Spinal commissural axons, which derive from the dorsal part of the neural tube (alar plate), initially project ventrally along the circumferential axis and then cross the ventral midline [10]. These axons have been shown to be guided by a diffusible molecule released... 

Hgure 3. Basic structure of the vertebrate central nervous system. The CNS is derived from a hollow structure called the neural tube. It has two orthogonal axes, the circumferential axis and the longidudinal axis. Four distinct domains called the roof, alar, basal, floor plates are generated along the circumferential axis (A). The neural tube can also divided along the longitudinal axis into the spinal cord and the brain, which can be further divided into five brain vesicles, the telencephalon, the diencephalon, the mesencephalon, the metencephalon and the myelencephalon (B). 

The development of in vitro brain slice and isolated neuron techniques has greatly facilitated detailed studies of the electrophysiology of a wide range of neuronal types in the adult and neonatal vertebrate central nervous system (CNS). Particularly advantageous are the greater mechanical stability that these preparations provide over in vivo models and the control allowed over the composition of the extracellular environment. In addition, the development of the patch-clamp technique has opened up the possibility of direct access to the intracellular environment via internal patch pipet solutions. In combination, these approaches have enabled detailed investigations of neuronal membrane properties, the cellular actions of neurotransmitters, and synaptic mechanisms. 

Section 3.1. describes application of the NADPH diaphorase method to fixed, whole nervous tissue. This approach has not been applied to vertebrate central nervous systems because they are simply too large and multilayered for it to be of any use m revealing NOS anatomy. It has been used in studies of the mammalian peripheral autonomic nervous system (15), but where the whole-mount staining method has proven especially useful is in the analysis of NOS anatomy in the smaller and simpler central nervous systems of invertebrates (10)... 

Johnson J L (1978) The excitant ammo acids, glutamic, and aspartic acids, as transmitter candidates m the vertebrate central nervous system. Prog, Neurohiol 10, 155-202. 

Before discussing the excitotoxins, the neurophysiologic effects of excitatory amino acids will be reviewed since this provides a conceptual background for understanding the mechanism of action of these compounds. More than 70 a-amino acids have been shown to have excitatory effects in the vertebrate central nervous system (Table 1) with the recent... 

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