Neuromuscular junction nitric oxide

Nitric oxide (NO) A cotransmitter at inhibitory ENS and other neuromuscular junctions may be especially important at sphincters. Synthesized on demand by nitric oxide synthase (NOS), not stored see Chapter 19. 

Substance P (related tachykinins) Substance P is an important sensory neuron transmitter in the ENS and elsewhere. Tachykinins appear to be excitatory cotransmitters with ACh at ENS neuromuscular junctions. Found with CGRP in cardiovascular sensory neurons. Substance P is a vasodilator (probably via release of nitric oxide). 

Syncoilin is highly expressed in skeletal and cardiac muscle and is localized to the neuromuscular junction, sarcolemma, and Z-lines. Likewise, desmuslin is expressed in heart and skeletal muscle and localized at Z-lines. It was shown that syncoilin and desmin interact directly, but do not coassemble into filaments in fact, evidence suggests that syncoilin does not participate in filament formation at all. It was proposed that syncoilin helps anchor the desmin IF network at the sarcolemma and the neuromuscular junction (Poon et al, 2002). More recent work has analyzed patients with a desmin-related cardiomyopathy in which patients with desmin accumulation also exhibit an upregulation of syncoilin and accumulation of other elements of the DPC. These defects were correlated with a disappearance of both o-dystrobrevin-l and neuronal nitric oxide... 

Localization and characterization of nitric oxide synthase at the frog neuromuscular junction. J Neurocytol 27 829-840. 

Etherington SJ, Everett AW. 2004. Postsynaptic production of nitric oxide implicated in long-term depression at the mature amphibian (Bufo marinns) neuromuscular junction. J Physiol 559 507-517. 

Godfrey EW, Schwarte RC. 2003. The role of nitric oxide signaling in the formation of the neuromuscular junction. J Neurocytol 32 591-602. 

Graves AR, Lewin KA, Lindgren C. 2004. Nitric oxide, cAMP and the biphasic muscarinic modulation of ACh release at the lizard neuromuscular junction. J Physiol 559 423-432. 

Schwarte RC, Godfrey EW. 2004. Nitric oxide synthase activity is required for postsynaptic differentiation of the embryonic neuromuscular junction. Dev Biol 273 276-284. 

Grozdanovic Z, Gossrau R (1998) Co-localization of nitric oxide synthase I (NOS I) and NMDA receptor subunit 1 (NMDAR-1) at the neuromuscular junction in rat and mouse skeletal muscle. Cell Tissue Res 297 57-63. 

The same cardiovascular control system regulates blood distribution and blood pressure by affecting the small arterioles of the peripheral blood vasculature. The entrance to each of these vessels is surrounded by a sphincter muscle (a ring of involuntary muscle that surrounds the arteriolar aperture) with sympathetic, and in some cases, parasympathetic, nerve fibers. The sphincter is usually contracted. When the signal comes for the muscle to relax, the neuron produces nitric oxide at the neuromuscular junction, and this gas relaxes the sphincter. When the sphincter muscle expands, it increases the area through which blood flows and decreases its resistance. With decreased resistance, blood pressure falls. 

Pinard, A., Robitaille, R., 2008. Nitric oxide dependence of glutamate-mediated modulation at a vertebrate neuromuscular junction. Eur. J. Neurosci. 28, 577-587. 

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