Heterogeneous systems peripheral

Lapierre YD, Browne M, Horn E, et al Treatment of major affective disorder with fluvoxamine. J Clin Psychiatry 48 65-68, 1987 Lapierre YD, Ravindran AV, Bakish D Dysthymia and serotonin. Int Clin Psychopharmacol 8 (suppl 2) 87-90, 1993 Lapin 1, Oxenkrug G Intensification of the central serotonergic process as a possible determinant of thymoleptic effect. Lancet 1 132-136, 1969 Larkin JG, McKee PJ, Blacklaw J, et al Nimodipine in refractory epilepsy a placebo-controlled, add-on study. Epilepsy Res 9 71-77, 1991 Larsson LI, Rehfeld JF Localization and molecular heterogeneity of cholecystokinin in the central and peripheral nervous system. Brain Res 165 201-218, 1979 Laruelle M, Abi-Dargham A, Casanova M, et al Selective abnormality of prefrontal serotonergic receptors in schizophrenia a post mortem study. Arch Gen Psychiatry 50 810-818, 1993... 

The heterogeneity of the periphery of the olfactory system is striking. What, if any, is the relationship between these overlapping, intricately orchestrated, patterns of gene expression and the ability of the peripheral olfactory system to encode odors ... 

The expression of onconeural antigens is highly restricted in some instances. Recoverin is found in the retinal cells only, and cdr2 expression is restricted to the Purkinje cells and brain stem. Other antigens such as Nova are widely distributed in the CNS, whereas the HuD and CRMP-5 antigens are expressed by neurons of both the CNS and the peripheral nervous system. The extensive immunoreactivity is reflected by the heterogenous clinical manifestations in patients with Ri, CRMP-5, Hu, and amphiphysin antibodies [15,29, 30]. 

Polyneuropathy with both sensory and motor involvement is much more common among cancer patients than pure SN [83, 110, 111]. SCLC is the most common associated tumor, although other solid tumors may be found [112]. Sensory-motor neuropathy is a quite common paraneoplastic feature in patients with onconeural antibodies, especially Hu and CRMP-5 antibodies. The CRMP-5 antibody is particularly associated with SCLC and thymoma [30]. The CRMP-5 antibody binds to oligodendrocytes as well as to neurons in specific brain regions and the retina and Schwann cells of the peripheral nervous system. In accordance with this, the clinical characteristics are heterogeneous. Many patients exhibit mixed axonal and demye-linating sensory-motor neuropathy, optic neuritis, or cerebellar dysfynction [85, 113], as well as extrapyramidal symptoms (Chapter 5.3). 

The technical problems involved with any attempt to use analogously systematic research approaches to a potential transmitter in the central nervous system are great. Peripheral synapses can be isolated by microdissection, they can remain functional in an isolated profusion experimental situation for hours, and their activation can be manifested by clearly defined and measurable phenomena (such as the miniature end-plate potential or the contraction of smooth muscle). The central nervous system has little in the way of focal synaptic regions. The dendrites and the cell bodies of central neurons are densely covered with synapses, many of which may be of a chemically heterogenous nature. In addition, the extra-neuronal space is packed with a tangle of glia, closely approximating the membranous surfaces of nerve cells and possibly intrinsically important to their function. This makes the isolated, chemical manipulation of central synapses extremely difficult. (Mandell and Spooner 1968, p. 1443)... 

Postsynaptic nicotinic receptors in the peripheral nervous system are designated as (in autonomic ganglia) and N2 (at myoneural junctions). Nicotinic receptors are of the ion channel type. They are pentameric proteins that are composed of one, two, or more distinct subunits, each of which contains multiple membrane-spanning regions, and the individual subunits surround an internal channel (28). Nicotinic receptors are highly heterogeneous, and subcategorization has been difficult those in neuronal tissue are believed to... 

Intracellular nucleotides play an important role in enzyme and ion channel regulation as well as in energy metabolism and nucleic acid synthesis. There is now widespread appreciation that ATP (and other nucleotides) may so be released into the extracellular fluid by exocytosis from nerve terminals or secretory cells. Thus, extracellular ATP can act as a neurotransmitter or modulator in a variety of peripheral tissues and cells, in autonomic ganglia and in the central nervous system [1-3]. The responses to extracellular ATP are mediated via membrane-bound receptors, termed P2-purinoceptors. Evidence has accumulated indicating heterogeneity of P2-purinoceptors, and it has become apparent that ATP acts on at least five P2-purinoceptor subtypes, i.e. P2X> P2Y> P2U> 2T 2Z... 

Another key observation is that heterogeneous networking will mean that the core of the network will have to be based on an open architecture, for example, an IP backbone. This core will be very fast and will be surrounded by slower peripheral wireless networks. However, the openness of the core network will give rise to a number of security threats such as denial-of-service (DoS) attacks that we see in the Internet today. So security must also be integrated into future mobile networks to deal with these threats. Thus, future mobile systems must encompass communications, mobility, QoS, and security. A new framework is therefore required to build such systems. 

Nicotinic receptors of the vertebrate neuromuscular junction and the electric organs of fishes represent a single subtype, and are known as peripheral receptors. Nicotinic receptors are also found in autonomic ganglia and in the central nervous system, where they are collectively known as neuronal receptors. The latter are also gated cation channels, but structurally they are a heterogeneous group, and less well characterized than peripheral receptors. 

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